To investigate the involvement of central serotonergic system in behavioral sensitization to morphine in mice. Male Kunming mice were treated （i.p.） with saline or morphine 10 mg/kg twice daily for 3 d and then drug...To investigate the involvement of central serotonergic system in behavioral sensitization to morphine in mice. Male Kunming mice were treated （i.p.） with saline or morphine 10 mg/kg twice daily for 3 d and then drug manipulation was suspended for 5 d. On day 9, a challenge dose of morphine （10 mg/kg） was given and the locomotor activity was measured for 60 rain to confkrm the establishment of behavioral sensitization in mice. Moreover, 5-hydroxytryptophan （5-HTP）, a precursor of serotonin, at the doses of 20-80 mg/kg was given i.p. in combination with daily morphine treatment （induction）, during the morphine treatment suspension （transfer） or prior to the challenge dose of morphine （expression） and locomotor activity was measured on day 9 after the challenge dose of morphine. Twice daily of morphine injection induced robust behavioral sensitization in mice as evidenced by significantly higher locomotion on day 9 for multiple treatment with morphine than saline in mice. 5-HTP treatment selec- tively and dose-dependently blocked the induction, but not the transfer nor the expression of morphine induced behavioral sensitization. This study provides clear evidence that up-regulation of central serotonergic system may suppress the induction of morphine sensitization in mice.展开更多
AIM: To investigate whether the Chinese medicine Tong Xie Yao Fang(TXYF) improves dysfunction in an irritable bowel syndrome(IBS) rat model. METHODS: Thirty baby rats for IBS modeling were separated from mother rats(1...AIM: To investigate whether the Chinese medicine Tong Xie Yao Fang(TXYF) improves dysfunction in an irritable bowel syndrome(IBS) rat model. METHODS: Thirty baby rats for IBS modeling were separated from mother rats(1 h per day) from days 8 to 21, and the rectum was expanded by angioplasty from days 8 to 12. Ten normal rats were used as normal controls. We examined the effects of TXYF on defection frequency, colonic transit function and smooth muscle contraction, and the expression of 5-hydroxytryptamine(5-HT) and substance P(SP) in colonic and hypothalamus tissues by Western blot and RT-PCT techniques in both normal rats and IBS model rats with characterized visceral hypersensitivity.in normal rats and 4.5 ± 1.58 in IBS model rats(P < 0.001). However, the defecation frequency was significantly decreased(3.0 ± 1.25 vs 4.5 ± 1.58, P < 0.05), while the time(in seconds) of colon transit function was significantly increased(256.88 ± 20.32 vs 93.36 ± 17.28, P < 0.001) in IBS + TXYF group rats than in IBS group rats. Increased colonic smooth muscle tension and contract frequency in IBS model rats were significantly decreased by administration of TXYF. Exogenous agonist stimulants increased spontaneous activity and elicited contractions of colon smooth muscle in IBS model rats, and all of these actions were significantly reduced by TXYF involving 5-HT and SP down-regulation. CONCLUSION: TXYF can modulate the activity of the enteric nervous system and alter 5-HT and SP activities, which may contribute to the symptoms of IBS.展开更多
5-Hydroxytryptamine 2C(5-HT2C) receptor is one of the major targets of anti-obesity agents, due to its role in regulation of appetite. In the present study, the 70% EtO H extract of the roots of Bupleurum chinense was...5-Hydroxytryptamine 2C(5-HT2C) receptor is one of the major targets of anti-obesity agents, due to its role in regulation of appetite. In the present study, the 70% EtO H extract of the roots of Bupleurum chinense was revealed to have agonistic activity on 5-HT2 C receptor, and the subsequent bioassay-guided isolation led to identification of several saikosaponins as the active constituents with 5-HT2 C receptor agonistic activity in vitro and anti-obesity activity in vivo. The new compound, 22-oxosaikosaponin d(1), was determined by extensive spectroscopic analyses(HR-ESI-MS, IR, and 1D and 2D NMR). The primary structure-activity relationship study suggested that the intramolecular ether bond between C-13 and C-28 and the number of sugars at C-3 position were closely related to the 5-HT2 C receptor agonistic activity. Saikosaponin a(3), the main saponin in B. chinense, showed obviously agonistic activity on 5-HT2 C receptor with an EC50 value of 21.08 ± 0.33 μmol×L^(–1) in vitro and could reduce food intake by 39.1% and 69.2%, and weight gain by 13.6% and 16.4%, respectively, at 3.0 and 6.0 mg×kg^(–1) in vivo. This investigation provided valuable information for the potential use of B. chinense as anti-obesity agent.展开更多
BACKGROUND: Hepatic stellate cell (HSC) plays a key role in hepatic fibrosis. This study was undertaken to investigate the expression of 5-hydroxytamine receptors in HSC and the effect of 5-hydroxytamine on biological...BACKGROUND: Hepatic stellate cell (HSC) plays a key role in hepatic fibrosis. This study was undertaken to investigate the expression of 5-hydroxytamine receptors in HSC and the effect of 5-hydroxytamine on biological characteristics of HSC. METHODS: Liver ex vivo perfusion of collagenase and density gradient centrifugation were used to isolate HSCs. Reverse transcriptase polymerase chain reaction (RT-PCR) was used to detect the expression of 5-hydroxytamine receptor subtypes 1A, 2A, 2B and 3. Western blot hybridization was used to elucidate the effect of 5-hydroxytamine and its 2A receptor antagonist ketanserin and 3 receptor antagonist ondanosetron on the expression of transforming growth factor-β_1(TGF-β_1) and Smad4 in HSC. RESULTS: HSC expressed 5-hydroxytamine receptor subtypes 1A, 2A and 2B. 5-hydroxytamine significantly increased the expression of TGF-β_1, and Smad4 in HSC (P<0.05). This action can be antagonized by ketanserin, not by ondanosetron. CONCLUSIONS: HSC expresses 5-hydroxytamine receptors. 5-hydroxytamine could effect the biological characteristics of HSC through its receptor mediation, and may play a role in the pathogenesis of liver cirrhosis and portal hypertension.展开更多
Objective To investigate changes of 5-hydroxytryptamine （5-HT） and its synthesis rate-limiting enzyme tryp-tophan hydroxylase （TPH） in the ventral horn of spinal cord after exercise-induced fatigue, and to further...Objective To investigate changes of 5-hydroxytryptamine （5-HT） and its synthesis rate-limiting enzyme tryp-tophan hydroxylase （TPH） in the ventral horn of spinal cord after exercise-induced fatigue, and to further discuss the mecha- nism of exercise-induced central fatigue at spinal level. Methods Sixteen healthy adult Wistar rats were randomly divided into 2 groups： exercise-induced fatigue group and control group. Immunohistochemical staining for 5-HT and TPH in the ventral horn were performed and analysized quantitatively. The mean optic densities of 5-HT and TPH positive fibers or terminals were measured by computerized image analyzer. Results Both 5-HT and TPH positive fibers/terminals decreased in the exercise-induced fatigue group. The immunohistochemical staining was weaker and the mean optic densities decreased obviously in the fatigue group compared with those in the control group （P 〈 0.05）. Conclusion 5-HT and TPH in the ventral horn of spinal cord might be involved in exercise-induced fatigue.展开更多
Insomnia is a common sleep disorder without effective therapy and can affect a person's life.The mechanism of the disease is not completely understood.Hence,there is a need to understand the targets related to ins...Insomnia is a common sleep disorder without effective therapy and can affect a person's life.The mechanism of the disease is not completely understood.Hence,there is a need to understand the targets related to insomnia,in order to develop innovative therapies and new compounds.Recently,increasing interest has been focused on complementary and alternative medicines for treating or preventing insomnia.Research into their molecular components has revealed that their sedative and sleep-promoting properties rely on the interactions with various neurotransmitter systems in the brain.In this review,the role of 5-hydroxytryptamine(5-HT)in insomnia development is summarized,while a systematic analysis of studies is conducted to assess the mechanisms of herbal medicines on different 5-HT receptors subtypes,in order to provide reference for subsequent research.展开更多
BACKGROUND： The orbitofrontal cortex （OFC） is a brain region closely associated with emotion. 5-hydroxytryptamine （5-HT） has been shown to be involved in human depression. OBJECTIVE： To investigate OFC actions a...BACKGROUND： The orbitofrontal cortex （OFC） is a brain region closely associated with emotion. 5-hydroxytryptamine （5-HT） has been shown to be involved in human depression. OBJECTIVE： To investigate OFC actions and mechanisms of 5-HT and 5-HT1A receptor （5-HT1AR） in stress-induced depression.DESIGN, TIME AND SETTING： A randomized, controlled, animal experiment was performed at Laboratory of Neurobiology, College of Life Science, Shaanxi Normal University between May 2006 and March 2008. MATERIALS： 5-HT, p-chlorophenylalanine （PCPA, an inhibitor to tryptophan hydroxylase） and spiperone （5-HT1AR antagonist） were provided by Sigma, USA; rabbit anti-rat 5-HT1AR antibody was provided by Tianjin Haoyang Biological Manufacture. METHODS： A total of 40 male Sprague Dawley rats, aged 3 months, were randomly divided into five groups： control, model, 5-HT, spiperone ＋ 5-HT, and PCPA, with 8 rats in each group. Except for control group, rats in the other four groups were used to establish depression models by forced swimming for 15 minutes. At 30 minutes before forced swimming test, 0.5 pL of 5-HT （12.5 pg/pL）, PCPA （20 pg/pL）, spiperone （1.3 pg/pL） ＋ 5-HT （12.5 pg/pL, 10 minutes later）, and saline were respectively injected into the OFC of 5-HT, PCPA, spiperone ＋ 5-HT, and model groups, respectively. The control group received a saline microinjection into the OFC.MAIN OUTCOME MEASURES： Forced swimming and open field tests were employed to measure animal behaviors, and immunohistochemistry was used to analyze 5-HT1AR expression in the OFC, cingulate cortex, and piriform cortex. RESULTS： （1） Compared with the model group, 5-HT microinjection into the OFC prominently reduced immobility time in the forced swimming test and rearing in open field test （P 〈 0.05）; locomotion and grooming in open field test were increased, although there was no significance （P 〉 0.05）. Furthermore, following PCPA microinjection into the OFC （PCPA ＋ forced swimming stress）, immobility time in forced swimming test increased dramatically （P〈 0.01）, locomotion and rearing in open field test declined （P〈 0.05 and P 〈 0.01, respectively）. Compared with the 5-HT group, 5-HT1AR antagonist （spiperone ＋ 5-HT ＋ forced swimming stress） increased immobility time in forced swimming test （P 〈 0.01）, but decreased locomotion, rearing, and grooming in open field test. （2） Forced swimming stress markedly elevated 5-HT1AR expression in OFC, cingulate cortex, and piriform cortex （P〈 0.05 or P〈 0.01）. CONCLUSION： 5-HT improved stress-induced depression, and 5-HT anti-depression effects are primarily achieved via 5-HT1AR. Stress-induced up regulation of 5-HT1AR expression might be a compensatory mechanism for decreased 5-HT expression.展开更多
Many studies have shown that(5R)-5-hydroxytriptolide is the optimal modified analogue of triptolide, possessing comparable immunosuppressive activity but much lower cytotoxicity than triptolide. Whether(5R)-5-hydroxyt...Many studies have shown that(5R)-5-hydroxytriptolide is the optimal modified analogue of triptolide, possessing comparable immunosuppressive activity but much lower cytotoxicity than triptolide. Whether(5R)-5-hydroxytriptolide has preventive effects on neuroinflammation is unclear. This study was designed to pretreat primary astrocytes from the brains of neonatal Sprague-Dawley rats with 20, 100 and 500 nM(5R)-5-hydroxytriptolide for 1 hour before establishing an in vitro neuroinflammation model with 1.0 μg/mL lipopolysaccharide for 24 hours. The generation of nitric oxide was detected by Griess reagents. Astrocyte marker glial fibrillary acidic protein was measured by immunohistochemical staining. The levels of tumor necrosis factor-α and interleukin-1β in the culture supernatant were assayed by enzyme linked immunosorbent assay. Nuclear factor-κB/p65 expression was examined by immunofluorescence staining. The phosphorylation of inhibitor of nuclear factor IκB-α and the location of nuclear factor-κB/P65 were determined using western blot assay. Our data revealed that(5R)-5-hydroxytriptolide inhibited the generation of nitric oxide, tumor necrosis factor-α and interleukin-1β from primary astrocytes activated by lipopolysaccharide, decreased the positive reaction intensity of glial fibrillary acidic protein, reduced the expression of tumor necrosis factor alpha and interleukin-1β in culture supernatant, inhibited the phosphorylation of IκB-α and the translocation of nuclear factor-κB/P65 to the nucleus. These results have confirmed that(5R)-5-hydroxytriptolide inhibits lipopolysaccharide-induced glial inflammatory response and provides cytological experimental data for(5R)-5-hydroxytriptolide in the treatment of neurodegenerative diseases.展开更多
5-hydroxytryptamine contributes to the control of activities of the dilator muscle in the upper respiratory tract, and is derived from the raphe nuclei, in which the habenular nucleus exerts a sustaJned inhibitory eff...5-hydroxytryptamine contributes to the control of activities of the dilator muscle in the upper respiratory tract, and is derived from the raphe nuclei, in which the habenular nucleus exerts a sustaJned inhibitory effect. In the present study, respiratory motion curve of the genJoglossus muscle and peripheral 5-hydroxytryptamine changes were observed following L-glutamate stimulation of the habenular nucleus of adult Wistar rats. Results showed that the rats had apnea and decreased plasma 5-hydroxytryptamine content after the neurons in habenular nucleus were excited. Genioglossus muscle electromyogram amplitude and integral were significantly reduced. The genioglossus myoelectric activity and respiratory motion curve were similar to obstructive sleep apnea syndrome, thus confirming that the habenular nucleus is the key nucleus involved in the pathogenesis of obstructive sleep apnea syndrome, and is the primary regulated center in the raphe nuclei. Stimulation of the habenular nucleus may suppress 5-hydroxytryptamine release and result in apnea, which is similar to obstructive sleep apnea syndrome.展开更多
In the present study, electrical stimulation to the rat insular cortex induced apnea or respiratory disturbance, reduced amplitude of genioglossal electromyogram, and decreased electromyogram integrals. In addition, a...In the present study, electrical stimulation to the rat insular cortex induced apnea or respiratory disturbance, reduced amplitude of genioglossal electromyogram, and decreased electromyogram integrals. In addition, arterial blood gas analysis showed arterial blood acidosis, reduced pH values, increased alkali reserve negative values, decreased peripheral blood 5-hydroxytryptamine content, and increased 5-hydroxytryptamine expression in cerebellar Purkinje cells. Following lidocaine injection to block the habenular nucleus, abnormalities in breath, genioglossal electromyogram, and blood gas values disappeared, and peripheral blood 5-hydroxytryptamine content returned to levels prior to electric stimulation. However, 5-hydroxytryptamine expression in cerebellar Purkinje cells remained high. The results suggested that 5-hydroxytryptamine expression in Purkinje cells did not correlate with ventilation function involving insular cortex and habenular nucleus.展开更多
5-Hydroxytryptamine(5-HT)type 3 receptor(5-HT_(3)R)is the only type of ligand-gated ion channel in the 5-HT receptor family.Through the high permeability of Na+,K+,and Ca2+and activation of subsequent voltage-gated ca...5-Hydroxytryptamine(5-HT)type 3 receptor(5-HT_(3)R)is the only type of ligand-gated ion channel in the 5-HT receptor family.Through the high permeability of Na+,K+,and Ca2+and activation of subsequent voltage-gated calcium channels(VGCCs),5-HT_(3)R induces a rapid increase of neuronal excitability or the release of neurotransmitters from axon terminals in the central nervous system(CNS).5-HT_(3)Rs are widely expressed in the medial prefrontal cortex(mPFC),amygdala(AMYG),hippocampus(HIP),periaqueductal gray(PAG),and other brain regions closely associated with anxiety reactions.They have a bidirectional regulatory effect on anxiety reactions by acting on different types of cells in different brain regions.5-HT_(3)Rs mediate the activation of the cholecystokinin(CCK)system in the AMYG,and theγ-aminobutyric acid(GABA)“disinhibition”mechanism in the prelimbic area of the mPFC promotes anxiety by the activation of GABAergic intermediate inhibitory neurons(IINs).In contrast,a 5-HT_(3)R-induced GABA“disinhibition”mechanism in the infralimbic area of the mPFC and the ventral HIP produces anxiolytic effects.5-HT_(2)R-mediated regulation of anxiety reactions are also activated by 5-HT_(3)R-activated 5-HT release in the HIP and PAG.This provides a theoretical basis for the treatment of anxiety disorders or the production of anxiolytic drugs by targeting 5-HT_(3)Rs.However,given the circuit specific modulation of 5-HT_(3)Rs on emotion,systemic use of 5-HT_(3)R agonism or antagonism alone seems unlikely to remedy anxiety,which deeply hinders the current clinical application of 5-HT_(3)R drugs.Therefore,the exploitation of circuit targeting methods or a combined drug strategy might be a useful developmental approach in the future.展开更多
AIM: To study differences in the visceral sensitivity of the colonic mucosa between patients with diarrheapredominant irritable bowel syndrome(IBS-D) and those with ulcerative colitis(UC) in remission and to relate th...AIM: To study differences in the visceral sensitivity of the colonic mucosa between patients with diarrheapredominant irritable bowel syndrome(IBS-D) and those with ulcerative colitis(UC) in remission and to relate these differences with changes in the 5-hydroxytryptophan(5-HT) signaling pathway. METHODS: Gastrointestinal symptoms were used to determine the clinical symptom scores and rectal visceral sensitivity of patients with IBS-D and patients with UC in remission. Blood levels of 5-HT and5-hydroxyindoleacetic acid(5-HIAA) were measured using an HPLC-electrochemical detection system. The levels of 5-HT 3 receptor(3R), 4R, and 7R m RNAs in colonic biopsy samples were detected using reverse transcription-polymerase chain reaction. The protein expression of TPH1 was analyzed by Western blot and immunohistochemistry.RESULTS: Abdominal pain or discomfort, stool frequency, and the scores of these symptoms in combination with gastrointestinal symptoms were higher in the IBS-D and UC groups than in the control groups. However, no significant differences were observed between the IBS-D and UC remission groups. With respect to rectal visceral sensitivity, the UC remission and IBS-D groups showed a decrease in the initial perception threshold, defecating threshold and pain threshold. However, these groups exhibited significantly increased anorectal relaxation pressure. Tests examining the main indicators of the 5-HT signaling pathway showed that the plasma 5-HT levels, 5-HIAA concentrations, TPH1 expression in the colonic mucosa, and 5-HT3 R and 5-HT5 R expression were increased in both the IBS-D and the UC remission groups; no increases were observed with respect to 5-HT7 R expression.CONCLUSION: The IBS-D and UC groups showed similar clinical symptom scores, visceral sensitivity, and levels of serotonin signaling pathway indicators in the plasma and colonic mucosa. However, the pain threshold and 5-HT7 R expression in the colonic mucosa were significantly different between these groups. The results reveal that(1) IBS-D and UC are related to visceral sensitivity pathogenesis and the clinical manifestations of these conditions and(2) the observed differences in visceral hypersensitivity are possibly due to differences in levels of the 5-HT7 receptor, a component of the 5-HT signaling pathway.展开更多
Objective:The present study aimed to investigate the effect of seasonal variation on neurotransmitter release in the hippocampus of normal rats and rats with pineal excision.Methods:Two time points,the summer and wint...Objective:The present study aimed to investigate the effect of seasonal variation on neurotransmitter release in the hippocampus of normal rats and rats with pineal excision.Methods:Two time points,the summer and winter solstice,which are the longest and shortest days of the year,respectively,were selected.Male Spraguee Dawley rats that underwent a sham operation without pineal excision were included as a control group.The concentrations of 5-hydroxytryptamine(5-HT)andγ-aminobutyric acid(GABA)were determined by radioimmunoassays and enzyme-linked immunosorbent assays,respectively.Results:In the winter,the 5-HT and GABA levels in normal rats exhibited a significant difference compared with those in the operation group(P<.01).A difference was also noted in GABA levels between the normal group and the sham operation group(P<.05).The concentrations of 5-HT and GABA in the hippocampal tissues of the normal group exhibited a seasonal rhythm consisting of elevation during the summer and reduction during the winter(P<.01),while the GABA levels in the sham operation group exhibited a significant difference,with elevation during the summer and reduction during the winter(P<.01).In the operation group,GABA showed the same trend(P<.01).Conclusion:The seasonal rhythm of neurotransmitter secretion by the hippocampus(5-HT and GABA)consisted of elevation during the summer and reduction during the winter.During the winter,the pineal gland exhibited a reverse regulatory effect on the secretion of 5-HT and GABA in the hippocampus,and it exhibited seasonal selectivity with regard to the regulation of 5-HT.展开更多
[ Objective] To find the rule of 5-hydroxytryptamine （5-HT） synthesis and metabolism in peripheral blood of suckling piglets with aging. [ Method ] All of 15 British Large White pigs at 0, 5 and 15 d of age were sel...[ Objective] To find the rule of 5-hydroxytryptamine （5-HT） synthesis and metabolism in peripheral blood of suckling piglets with aging. [ Method ] All of 15 British Large White pigs at 0, 5 and 15 d of age were selected as experimental animals, and their serumal concentrations of L- tryptophan （L-Trp）, 5-HT and 5-hydroxyindoleacetic acid （5-HIAA） in peripheral circulatory system were determined synchronously by reversed- phase high-performance liquid chromatography method with UV. [ Result] The concentration of L-Trp was （16. 92 ± 1.74） iJmol/L at birth, （59.94 ±10.88） iJmol/L at 5 d of age and （70.42± 6.48） μmol/L at 15 d of age. The concentration of 5-HT was （ 12.85 ± 1.79） iJmol/L at birth, （4.81 ±2.05） ijmol/L at 5 d of age and （5.49±1.09） μmol/L at 15 d of age. While 5-HIAA, the metabolic product of 5-HT, was not detected at all the samples selected. [ Conclusion] The L-Trp concentration of suckling piglets increase significantly with aging （ P 〈0. 05）. While the concentra- tion of 5-HT and the conversion ratio of L-Trp to 5-HT are both highest at birth （P〈0.05） and keep stable at 5 and 15 d of age.展开更多
The contents of 5-hydroxytryptamine(5-HT)and dopamine(DA) in the brain microvessels(BMVs) at the early stage of rat brain injury were measured by using high performance liquid chromatography with electrochemical detec...The contents of 5-hydroxytryptamine(5-HT)and dopamine(DA) in the brain microvessels(BMVs) at the early stage of rat brain injury were measured by using high performance liquid chromatography with electrochemical detector(HPLC-ECD) and the influence of the展开更多
Previous studies have indicated that the pathogenesis of amyotrophic lateral sclerosis(ALS) is closely linked to 5-hydroxytryptamine(5-HT).To investigate this further,we administered 5-HT receptor antagonists to SOD1*...Previous studies have indicated that the pathogenesis of amyotrophic lateral sclerosis(ALS) is closely linked to 5-hydroxytryptamine(5-HT).To investigate this further,we administered 5-HT receptor antagonists to SOD1*G93A transgenic(ALS mouse model) and wide-type mice.This involved intraperitoneal injections of either granisetron,piboserod,or ritanserin,which inhibit the 5-HT3,5-HT4,and 5-HT2 receptors,respectively.The transgenic mice were found to have fewer5-HT-positive cells in the spinal cord compared with wide-type mice.We found that the administration of granisetron reduced the body weight of the transgenic mice,while piboserod and ritanserin worsened the motor functioning,as assessed using a hanging wire test.However,none of the 5-HT receptor antagonists affected the disease progression.We analyzed the distribution and/or expression of TAR DNA binding protein 43(TDP-43) and superoxide dismutase 1 G93A(SOD1-G93A),which fo rm abnormal aggregates in ALS.We found that the expression of these proteins increased following the administration of all three 5-HT receptor antagonists.In addition,the disease-related mislocalization of TD P-43 to the cytoplasm increased markedly for all three drugs.In ce rtain anatomical regions,the 5-HT receptor antagonists also led to a marked increase in the number of astrocytes and microglia and a decrease in the number of neurons.These results indicate that 5-HT deficiency may play a role in the pathogenesis of amyotrophic lateral sclerosis by inducing the abnormal expression and/or distribution of TDP-43 and SOD1-G93A and by activating glial cells.5-HT co uld therefore be a potential therapeutic target for amyotrophic lateral sclerosis.展开更多
This study aimed to seek necrosis avid agents with high safety from DNA binding agents.The interaction of 5-hydroxytryptophan(5-HTP)with DNA was investigated by a series of spectroscopic studies.Then,5-HTP was labeled...This study aimed to seek necrosis avid agents with high safety from DNA binding agents.The interaction of 5-hydroxytryptophan(5-HTP)with DNA was investigated by a series of spectroscopic studies.Then,5-HTP was labeled with iodine-131([^(131)I]5-HTP)and the necrosis avidity of[^(131)I]5-HTP was evaluated by in vitro cell binding assays,in vivo biodistribution experiments and blocking experiment.Finally,the potential of[^(131)I]5-HTP to image necrotic myocardium was explored in rat models with myocardial infarction by SPECT/CT imaging.Results showed that 5-HTP bound to DNA in groove binding mode and the binding constant was 1.69×10~4 L/mol.[~(^(131))I]5-HTP showed specific affinity to necrotic A549 cells,which might be related to cell nucleus.Biodistribution and autoradiography results showed preferential accumulation of[^(131)I]5-HTP in necrotic muscle(necrotic/viable muscle ratio:6.95?0.68 at 3 h postinjection(p.i.)),which could be blocked by 5-HTP with 66.7%decline,indicating that[^(131)I]5-HTP might share the same necrotic targets with 5-HTP.On SPECT/CT images,a hotspot was clearly observed at 3h p.i.in the necrotic myocardium while not in the control myocardium.In conclusion,[^(131)I]5-HTP is a novel necrosis avid agent and can rapidly visualize necrotic myocardium at 3 h p.i.The necrosis avidity mechanism of[^(131)I]5-HTP may be attributed to its interactions with exposed DNA in the necrotic tissues.展开更多
In the first and second parts of this study,5-hydroxytryptamine(5HT)receptors,including 5-HT3 and 5-HT4 with the highest expression level,were found in clasp and sling fibres of the lower esophageal sphincter(LES).Spe...In the first and second parts of this study,5-hydroxytryptamine(5HT)receptors,including 5-HT3 and 5-HT4 with the highest expression level,were found in clasp and sling fibres of the lower esophageal sphincter(LES).Specific 5-HT3 and 5-HT4 receptor agonists can induce the contraction effect of clasp and sling fibres of the LES while specific 5-HT7 receptor agonists showed no effects.In the study of this part,the in-vitro muscle tension measurement technology and EFS methods were used to detect the effect of the selective 5-HT receptor antagonist on the clasp and sling fibres of the in-vitro LES under the electrical field stimulation(EFS),and further to ensure the effect of 5-HT receptor in the LES neuroregulatory pathway,and deeply explore the effect of 5-HT receptor in the systolic and diastolic function regulation of the LES.展开更多
Extracellular amyloid beta(Aβ) plaques are main pathological feature of Alzheimer’s disease.However,the specific type of neuro ns that produce Aβ peptides in the initial stage of Alzheimer’s disease are unknown.In...Extracellular amyloid beta(Aβ) plaques are main pathological feature of Alzheimer’s disease.However,the specific type of neuro ns that produce Aβ peptides in the initial stage of Alzheimer’s disease are unknown.In this study,we found that 5-hydroxytryptamin receptor 3A subunit(HTR3A) was highly expressed in the brain tissue of transgenic amyloid precursor protein and presenilin-1 mice(an Alzheimer’s disease model) and patients with Alzheimer’s disease.To investigate whether HTR3A-positive interneurons are associated with the production of Aβ plaques,we performed double immunostaining and found that HTR3A-positive interneurons were clustered around Aβ plaques in the mouse model.Some amyloid precursor protein-positive or β-site amyloid precursor protein cleaving enzyme-1-positive neurites near Aβ plaques were co-localized with HTR3A interneurons.These results suggest that HTR3A-positive interneurons may partially contribute to the generation of Aβ peptides.We treated 5.0-5.5-month-old model mice with tro pisetron,a HTR3 antagonist,for 8 consecutive weeks.We found that the cognitive deficit of mice was partially reversed,Aβ plaques and neuroinflammation we re remarkably reduced,the expression of HTR3 was remarkably decreased and the calcineurin/nuclear factor of activated T-cell 4 signaling pathway was inhibited in treated model mice.These findings suggest that HTR3A interneurons partly contribute to generation of Aβ peptide at the initial stage of Alzheimer’s disease and inhibiting HTR3 partly reve rses the pathological changes of Alzheimer’s disease.展开更多
As a neurotransmitter and avascular active substance,the 5-hydroxytryptamine(5-HT,serotonin)is widely distributed in the central nervous system and surrounding tissues.The 5-HT can play its role by acting on its corre...As a neurotransmitter and avascular active substance,the 5-hydroxytryptamine(5-HT,serotonin)is widely distributed in the central nervous system and surrounding tissues.The 5-HT can play its role by acting on its corresponding 5-HT receptor.Nowadays,the 5-HT receptor can be classified into seven,according to different signal transduction method of receptors,the 5-HT3 receptor belongs to the ligandgated ion channels,while other six 5-HT receptors are involved into the G protein-coupled receptors and play the biological role by binding to specific G protein-coupled receptors(GPCRs)on the surface of the cell membrane.The 5-HT plays an important role in the brain-gut information transmission and studies showed that the physiological stimulations like having meals,and pathological stimulations like ischemia and stress could promote the release of the 5-HT.In the gastrointestinal tract,the 5-HT is closely related to gastrointestinal sensitivity,gastrointestinal movement and secretion regulation,as well as many gastrointestinal dysfunction disorders,such as gastrointestinal power and visceral sensitivity abnormality and abnormalities of brain-gut axis.展开更多
基金National Natural Science Foundation of China (Grant No. 30570653)National Basic Research Program of China (Grant No. 2003CB515400)985 Program of China Ministry of Education
文摘To investigate the involvement of central serotonergic system in behavioral sensitization to morphine in mice. Male Kunming mice were treated （i.p.） with saline or morphine 10 mg/kg twice daily for 3 d and then drug manipulation was suspended for 5 d. On day 9, a challenge dose of morphine （10 mg/kg） was given and the locomotor activity was measured for 60 rain to confkrm the establishment of behavioral sensitization in mice. Moreover, 5-hydroxytryptophan （5-HTP）, a precursor of serotonin, at the doses of 20-80 mg/kg was given i.p. in combination with daily morphine treatment （induction）, during the morphine treatment suspension （transfer） or prior to the challenge dose of morphine （expression） and locomotor activity was measured on day 9 after the challenge dose of morphine. Twice daily of morphine injection induced robust behavioral sensitization in mice as evidenced by significantly higher locomotion on day 9 for multiple treatment with morphine than saline in mice. 5-HTP treatment selec- tively and dose-dependently blocked the induction, but not the transfer nor the expression of morphine induced behavioral sensitization. This study provides clear evidence that up-regulation of central serotonergic system may suppress the induction of morphine sensitization in mice.
基金Supported by National Education Department"ChunHui Plan"Research Projects,No.Z2010021China Postdoctoral Science Foundation Project,No.2013M531079+2 种基金Heilongjiang Postdoctoral Funding Project,No.LBH-Z12246Heilongjiang Education Department Scientific Research Project,No.12521502excellent Innovative Talents Support Program Funding of Heilongjiang University of Chinese Medicine(Outstanding Young Academic Leaders),No.051217
文摘AIM: To investigate whether the Chinese medicine Tong Xie Yao Fang(TXYF) improves dysfunction in an irritable bowel syndrome(IBS) rat model. METHODS: Thirty baby rats for IBS modeling were separated from mother rats(1 h per day) from days 8 to 21, and the rectum was expanded by angioplasty from days 8 to 12. Ten normal rats were used as normal controls. We examined the effects of TXYF on defection frequency, colonic transit function and smooth muscle contraction, and the expression of 5-hydroxytryptamine(5-HT) and substance P(SP) in colonic and hypothalamus tissues by Western blot and RT-PCT techniques in both normal rats and IBS model rats with characterized visceral hypersensitivity.in normal rats and 4.5 ± 1.58 in IBS model rats(P < 0.001). However, the defecation frequency was significantly decreased(3.0 ± 1.25 vs 4.5 ± 1.58, P < 0.05), while the time(in seconds) of colon transit function was significantly increased(256.88 ± 20.32 vs 93.36 ± 17.28, P < 0.001) in IBS + TXYF group rats than in IBS group rats. Increased colonic smooth muscle tension and contract frequency in IBS model rats were significantly decreased by administration of TXYF. Exogenous agonist stimulants increased spontaneous activity and elicited contractions of colon smooth muscle in IBS model rats, and all of these actions were significantly reduced by TXYF involving 5-HT and SP down-regulation. CONCLUSION: TXYF can modulate the activity of the enteric nervous system and alter 5-HT and SP activities, which may contribute to the symptoms of IBS.
基金supported by the National Science Foundation of China(No.81573322)the Hundred-Talent Program of CAS+1 种基金the CAS"Light of West China"Programthe Youth Innovation Promotion Association of CAS
文摘5-Hydroxytryptamine 2C(5-HT2C) receptor is one of the major targets of anti-obesity agents, due to its role in regulation of appetite. In the present study, the 70% EtO H extract of the roots of Bupleurum chinense was revealed to have agonistic activity on 5-HT2 C receptor, and the subsequent bioassay-guided isolation led to identification of several saikosaponins as the active constituents with 5-HT2 C receptor agonistic activity in vitro and anti-obesity activity in vivo. The new compound, 22-oxosaikosaponin d(1), was determined by extensive spectroscopic analyses(HR-ESI-MS, IR, and 1D and 2D NMR). The primary structure-activity relationship study suggested that the intramolecular ether bond between C-13 and C-28 and the number of sugars at C-3 position were closely related to the 5-HT2 C receptor agonistic activity. Saikosaponin a(3), the main saponin in B. chinense, showed obviously agonistic activity on 5-HT2 C receptor with an EC50 value of 21.08 ± 0.33 μmol×L^(–1) in vitro and could reduce food intake by 39.1% and 69.2%, and weight gain by 13.6% and 16.4%, respectively, at 3.0 and 6.0 mg×kg^(–1) in vivo. This investigation provided valuable information for the potential use of B. chinense as anti-obesity agent.
基金This study was supported by a grant from the National Natural Science Foundation of China (No. 39970722).
文摘BACKGROUND: Hepatic stellate cell (HSC) plays a key role in hepatic fibrosis. This study was undertaken to investigate the expression of 5-hydroxytamine receptors in HSC and the effect of 5-hydroxytamine on biological characteristics of HSC. METHODS: Liver ex vivo perfusion of collagenase and density gradient centrifugation were used to isolate HSCs. Reverse transcriptase polymerase chain reaction (RT-PCR) was used to detect the expression of 5-hydroxytamine receptor subtypes 1A, 2A, 2B and 3. Western blot hybridization was used to elucidate the effect of 5-hydroxytamine and its 2A receptor antagonist ketanserin and 3 receptor antagonist ondanosetron on the expression of transforming growth factor-β_1(TGF-β_1) and Smad4 in HSC. RESULTS: HSC expressed 5-hydroxytamine receptor subtypes 1A, 2A and 2B. 5-hydroxytamine significantly increased the expression of TGF-β_1, and Smad4 in HSC (P<0.05). This action can be antagonized by ketanserin, not by ondanosetron. CONCLUSIONS: HSC expresses 5-hydroxytamine receptors. 5-hydroxytamine could effect the biological characteristics of HSC through its receptor mediation, and may play a role in the pathogenesis of liver cirrhosis and portal hypertension.
文摘Objective To investigate changes of 5-hydroxytryptamine （5-HT） and its synthesis rate-limiting enzyme tryp-tophan hydroxylase （TPH） in the ventral horn of spinal cord after exercise-induced fatigue, and to further discuss the mecha- nism of exercise-induced central fatigue at spinal level. Methods Sixteen healthy adult Wistar rats were randomly divided into 2 groups： exercise-induced fatigue group and control group. Immunohistochemical staining for 5-HT and TPH in the ventral horn were performed and analysized quantitatively. The mean optic densities of 5-HT and TPH positive fibers or terminals were measured by computerized image analyzer. Results Both 5-HT and TPH positive fibers/terminals decreased in the exercise-induced fatigue group. The immunohistochemical staining was weaker and the mean optic densities decreased obviously in the fatigue group compared with those in the control group （P 〈 0.05）. Conclusion 5-HT and TPH in the ventral horn of spinal cord might be involved in exercise-induced fatigue.
基金supported by the National Natural Science Foundation of China(Nos.82174091,82122066,81973291,and 82003909)the National Key R&D Program of China(No.2022YFC2704603).
文摘Insomnia is a common sleep disorder without effective therapy and can affect a person's life.The mechanism of the disease is not completely understood.Hence,there is a need to understand the targets related to insomnia,in order to develop innovative therapies and new compounds.Recently,increasing interest has been focused on complementary and alternative medicines for treating or preventing insomnia.Research into their molecular components has revealed that their sedative and sleep-promoting properties rely on the interactions with various neurotransmitter systems in the brain.In this review,the role of 5-hydroxytryptamine(5-HT)in insomnia development is summarized,while a systematic analysis of studies is conducted to assess the mechanisms of herbal medicines on different 5-HT receptors subtypes,in order to provide reference for subsequent research.
基金the Natural Science Foundation of Shaanxi Province,No. 2006C240
文摘BACKGROUND： The orbitofrontal cortex （OFC） is a brain region closely associated with emotion. 5-hydroxytryptamine （5-HT） has been shown to be involved in human depression. OBJECTIVE： To investigate OFC actions and mechanisms of 5-HT and 5-HT1A receptor （5-HT1AR） in stress-induced depression.DESIGN, TIME AND SETTING： A randomized, controlled, animal experiment was performed at Laboratory of Neurobiology, College of Life Science, Shaanxi Normal University between May 2006 and March 2008. MATERIALS： 5-HT, p-chlorophenylalanine （PCPA, an inhibitor to tryptophan hydroxylase） and spiperone （5-HT1AR antagonist） were provided by Sigma, USA; rabbit anti-rat 5-HT1AR antibody was provided by Tianjin Haoyang Biological Manufacture. METHODS： A total of 40 male Sprague Dawley rats, aged 3 months, were randomly divided into five groups： control, model, 5-HT, spiperone ＋ 5-HT, and PCPA, with 8 rats in each group. Except for control group, rats in the other four groups were used to establish depression models by forced swimming for 15 minutes. At 30 minutes before forced swimming test, 0.5 pL of 5-HT （12.5 pg/pL）, PCPA （20 pg/pL）, spiperone （1.3 pg/pL） ＋ 5-HT （12.5 pg/pL, 10 minutes later）, and saline were respectively injected into the OFC of 5-HT, PCPA, spiperone ＋ 5-HT, and model groups, respectively. The control group received a saline microinjection into the OFC.MAIN OUTCOME MEASURES： Forced swimming and open field tests were employed to measure animal behaviors, and immunohistochemistry was used to analyze 5-HT1AR expression in the OFC, cingulate cortex, and piriform cortex. RESULTS： （1） Compared with the model group, 5-HT microinjection into the OFC prominently reduced immobility time in the forced swimming test and rearing in open field test （P 〈 0.05）; locomotion and grooming in open field test were increased, although there was no significance （P 〉 0.05）. Furthermore, following PCPA microinjection into the OFC （PCPA ＋ forced swimming stress）, immobility time in forced swimming test increased dramatically （P〈 0.01）, locomotion and rearing in open field test declined （P〈 0.05 and P 〈 0.01, respectively）. Compared with the 5-HT group, 5-HT1AR antagonist （spiperone ＋ 5-HT ＋ forced swimming stress） increased immobility time in forced swimming test （P 〈 0.01）, but decreased locomotion, rearing, and grooming in open field test. （2） Forced swimming stress markedly elevated 5-HT1AR expression in OFC, cingulate cortex, and piriform cortex （P〈 0.05 or P〈 0.01）. CONCLUSION： 5-HT improved stress-induced depression, and 5-HT anti-depression effects are primarily achieved via 5-HT1AR. Stress-induced up regulation of 5-HT1AR expression might be a compensatory mechanism for decreased 5-HT expression.
基金supported by the National Natural Science Foundation of China,No.81402932(to YQC)
文摘Many studies have shown that(5R)-5-hydroxytriptolide is the optimal modified analogue of triptolide, possessing comparable immunosuppressive activity but much lower cytotoxicity than triptolide. Whether(5R)-5-hydroxytriptolide has preventive effects on neuroinflammation is unclear. This study was designed to pretreat primary astrocytes from the brains of neonatal Sprague-Dawley rats with 20, 100 and 500 nM(5R)-5-hydroxytriptolide for 1 hour before establishing an in vitro neuroinflammation model with 1.0 μg/mL lipopolysaccharide for 24 hours. The generation of nitric oxide was detected by Griess reagents. Astrocyte marker glial fibrillary acidic protein was measured by immunohistochemical staining. The levels of tumor necrosis factor-α and interleukin-1β in the culture supernatant were assayed by enzyme linked immunosorbent assay. Nuclear factor-κB/p65 expression was examined by immunofluorescence staining. The phosphorylation of inhibitor of nuclear factor IκB-α and the location of nuclear factor-κB/P65 were determined using western blot assay. Our data revealed that(5R)-5-hydroxytriptolide inhibited the generation of nitric oxide, tumor necrosis factor-α and interleukin-1β from primary astrocytes activated by lipopolysaccharide, decreased the positive reaction intensity of glial fibrillary acidic protein, reduced the expression of tumor necrosis factor alpha and interleukin-1β in culture supernatant, inhibited the phosphorylation of IκB-α and the translocation of nuclear factor-κB/P65 to the nucleus. These results have confirmed that(5R)-5-hydroxytriptolide inhibits lipopolysaccharide-induced glial inflammatory response and provides cytological experimental data for(5R)-5-hydroxytriptolide in the treatment of neurodegenerative diseases.
基金the National Natural Science Foundation of China, No. 30270502
文摘5-hydroxytryptamine contributes to the control of activities of the dilator muscle in the upper respiratory tract, and is derived from the raphe nuclei, in which the habenular nucleus exerts a sustaJned inhibitory effect. In the present study, respiratory motion curve of the genJoglossus muscle and peripheral 5-hydroxytryptamine changes were observed following L-glutamate stimulation of the habenular nucleus of adult Wistar rats. Results showed that the rats had apnea and decreased plasma 5-hydroxytryptamine content after the neurons in habenular nucleus were excited. Genioglossus muscle electromyogram amplitude and integral were significantly reduced. The genioglossus myoelectric activity and respiratory motion curve were similar to obstructive sleep apnea syndrome, thus confirming that the habenular nucleus is the key nucleus involved in the pathogenesis of obstructive sleep apnea syndrome, and is the primary regulated center in the raphe nuclei. Stimulation of the habenular nucleus may suppress 5-hydroxytryptamine release and result in apnea, which is similar to obstructive sleep apnea syndrome.
基金supported by the National Natural Science Foundation of China, No. 30270502
文摘In the present study, electrical stimulation to the rat insular cortex induced apnea or respiratory disturbance, reduced amplitude of genioglossal electromyogram, and decreased electromyogram integrals. In addition, arterial blood gas analysis showed arterial blood acidosis, reduced pH values, increased alkali reserve negative values, decreased peripheral blood 5-hydroxytryptamine content, and increased 5-hydroxytryptamine expression in cerebellar Purkinje cells. Following lidocaine injection to block the habenular nucleus, abnormalities in breath, genioglossal electromyogram, and blood gas values disappeared, and peripheral blood 5-hydroxytryptamine content returned to levels prior to electric stimulation. However, 5-hydroxytryptamine expression in cerebellar Purkinje cells remained high. The results suggested that 5-hydroxytryptamine expression in Purkinje cells did not correlate with ventilation function involving insular cortex and habenular nucleus.
基金supported by the National Natural Science Foundation of China(Nos.82071516,32171065,91949105,and 81771227)the Innovation Capability Support Program of Shannxi Province in China(No.2020TD-037)the Fundamental Research Funds for the Central Universities(Nos.GK202105001,GK202205019,and CK202205022),China.
文摘5-Hydroxytryptamine(5-HT)type 3 receptor(5-HT_(3)R)is the only type of ligand-gated ion channel in the 5-HT receptor family.Through the high permeability of Na+,K+,and Ca2+and activation of subsequent voltage-gated calcium channels(VGCCs),5-HT_(3)R induces a rapid increase of neuronal excitability or the release of neurotransmitters from axon terminals in the central nervous system(CNS).5-HT_(3)Rs are widely expressed in the medial prefrontal cortex(mPFC),amygdala(AMYG),hippocampus(HIP),periaqueductal gray(PAG),and other brain regions closely associated with anxiety reactions.They have a bidirectional regulatory effect on anxiety reactions by acting on different types of cells in different brain regions.5-HT_(3)Rs mediate the activation of the cholecystokinin(CCK)system in the AMYG,and theγ-aminobutyric acid(GABA)“disinhibition”mechanism in the prelimbic area of the mPFC promotes anxiety by the activation of GABAergic intermediate inhibitory neurons(IINs).In contrast,a 5-HT_(3)R-induced GABA“disinhibition”mechanism in the infralimbic area of the mPFC and the ventral HIP produces anxiolytic effects.5-HT_(2)R-mediated regulation of anxiety reactions are also activated by 5-HT_(3)R-activated 5-HT release in the HIP and PAG.This provides a theoretical basis for the treatment of anxiety disorders or the production of anxiolytic drugs by targeting 5-HT_(3)Rs.However,given the circuit specific modulation of 5-HT_(3)Rs on emotion,systemic use of 5-HT_(3)R agonism or antagonism alone seems unlikely to remedy anxiety,which deeply hinders the current clinical application of 5-HT_(3)R drugs.Therefore,the exploitation of circuit targeting methods or a combined drug strategy might be a useful developmental approach in the future.
基金Supported by The Natural Science Foundation of Guangdong,No.S2012040006557
文摘AIM: To study differences in the visceral sensitivity of the colonic mucosa between patients with diarrheapredominant irritable bowel syndrome(IBS-D) and those with ulcerative colitis(UC) in remission and to relate these differences with changes in the 5-hydroxytryptophan(5-HT) signaling pathway. METHODS: Gastrointestinal symptoms were used to determine the clinical symptom scores and rectal visceral sensitivity of patients with IBS-D and patients with UC in remission. Blood levels of 5-HT and5-hydroxyindoleacetic acid(5-HIAA) were measured using an HPLC-electrochemical detection system. The levels of 5-HT 3 receptor(3R), 4R, and 7R m RNAs in colonic biopsy samples were detected using reverse transcription-polymerase chain reaction. The protein expression of TPH1 was analyzed by Western blot and immunohistochemistry.RESULTS: Abdominal pain or discomfort, stool frequency, and the scores of these symptoms in combination with gastrointestinal symptoms were higher in the IBS-D and UC groups than in the control groups. However, no significant differences were observed between the IBS-D and UC remission groups. With respect to rectal visceral sensitivity, the UC remission and IBS-D groups showed a decrease in the initial perception threshold, defecating threshold and pain threshold. However, these groups exhibited significantly increased anorectal relaxation pressure. Tests examining the main indicators of the 5-HT signaling pathway showed that the plasma 5-HT levels, 5-HIAA concentrations, TPH1 expression in the colonic mucosa, and 5-HT3 R and 5-HT5 R expression were increased in both the IBS-D and the UC remission groups; no increases were observed with respect to 5-HT7 R expression.CONCLUSION: The IBS-D and UC groups showed similar clinical symptom scores, visceral sensitivity, and levels of serotonin signaling pathway indicators in the plasma and colonic mucosa. However, the pain threshold and 5-HT7 R expression in the colonic mucosa were significantly different between these groups. The results reveal that(1) IBS-D and UC are related to visceral sensitivity pathogenesis and the clinical manifestations of these conditions and(2) the observed differences in visceral hypersensitivity are possibly due to differences in levels of the 5-HT7 receptor, a component of the 5-HT signaling pathway.
基金the National Natural Science Foundation of China(81774162)。
文摘Objective:The present study aimed to investigate the effect of seasonal variation on neurotransmitter release in the hippocampus of normal rats and rats with pineal excision.Methods:Two time points,the summer and winter solstice,which are the longest and shortest days of the year,respectively,were selected.Male Spraguee Dawley rats that underwent a sham operation without pineal excision were included as a control group.The concentrations of 5-hydroxytryptamine(5-HT)andγ-aminobutyric acid(GABA)were determined by radioimmunoassays and enzyme-linked immunosorbent assays,respectively.Results:In the winter,the 5-HT and GABA levels in normal rats exhibited a significant difference compared with those in the operation group(P<.01).A difference was also noted in GABA levels between the normal group and the sham operation group(P<.05).The concentrations of 5-HT and GABA in the hippocampal tissues of the normal group exhibited a seasonal rhythm consisting of elevation during the summer and reduction during the winter(P<.01),while the GABA levels in the sham operation group exhibited a significant difference,with elevation during the summer and reduction during the winter(P<.01).In the operation group,GABA showed the same trend(P<.01).Conclusion:The seasonal rhythm of neurotransmitter secretion by the hippocampus(5-HT and GABA)consisted of elevation during the summer and reduction during the winter.During the winter,the pineal gland exhibited a reverse regulatory effect on the secretion of 5-HT and GABA in the hippocampus,and it exhibited seasonal selectivity with regard to the regulation of 5-HT.
基金funding from " Eleventh Five-Year" National Science and Technology Support Program of China (2007BAD86B-06)
文摘[ Objective] To find the rule of 5-hydroxytryptamine （5-HT） synthesis and metabolism in peripheral blood of suckling piglets with aging. [ Method ] All of 15 British Large White pigs at 0, 5 and 15 d of age were selected as experimental animals, and their serumal concentrations of L- tryptophan （L-Trp）, 5-HT and 5-hydroxyindoleacetic acid （5-HIAA） in peripheral circulatory system were determined synchronously by reversed- phase high-performance liquid chromatography method with UV. [ Result] The concentration of L-Trp was （16. 92 ± 1.74） iJmol/L at birth, （59.94 ±10.88） iJmol/L at 5 d of age and （70.42± 6.48） μmol/L at 15 d of age. The concentration of 5-HT was （ 12.85 ± 1.79） iJmol/L at birth, （4.81 ±2.05） ijmol/L at 5 d of age and （5.49±1.09） μmol/L at 15 d of age. While 5-HIAA, the metabolic product of 5-HT, was not detected at all the samples selected. [ Conclusion] The L-Trp concentration of suckling piglets increase significantly with aging （ P 〈0. 05）. While the concentra- tion of 5-HT and the conversion ratio of L-Trp to 5-HT are both highest at birth （P〈0.05） and keep stable at 5 and 15 d of age.
文摘The contents of 5-hydroxytryptamine(5-HT)and dopamine(DA) in the brain microvessels(BMVs) at the early stage of rat brain injury were measured by using high performance liquid chromatography with electrochemical detector(HPLC-ECD) and the influence of the
基金supported by the National Natural Science Foundation of China,Nos.30560042,81160161,8136019882160255+2 种基金Education Department of Jiangxi Province,Nos.GJJ13198 and GJJ170021Jiangxi Provincial Department of Science and Technology,Nos.20142BBG70062,20171 BAB215022,20192BAB205043Health and Family Planning Commission of Jiangxi Province,No.20181019 (all to RSX)。
文摘Previous studies have indicated that the pathogenesis of amyotrophic lateral sclerosis(ALS) is closely linked to 5-hydroxytryptamine(5-HT).To investigate this further,we administered 5-HT receptor antagonists to SOD1*G93A transgenic(ALS mouse model) and wide-type mice.This involved intraperitoneal injections of either granisetron,piboserod,or ritanserin,which inhibit the 5-HT3,5-HT4,and 5-HT2 receptors,respectively.The transgenic mice were found to have fewer5-HT-positive cells in the spinal cord compared with wide-type mice.We found that the administration of granisetron reduced the body weight of the transgenic mice,while piboserod and ritanserin worsened the motor functioning,as assessed using a hanging wire test.However,none of the 5-HT receptor antagonists affected the disease progression.We analyzed the distribution and/or expression of TAR DNA binding protein 43(TDP-43) and superoxide dismutase 1 G93A(SOD1-G93A),which fo rm abnormal aggregates in ALS.We found that the expression of these proteins increased following the administration of all three 5-HT receptor antagonists.In addition,the disease-related mislocalization of TD P-43 to the cytoplasm increased markedly for all three drugs.In ce rtain anatomical regions,the 5-HT receptor antagonists also led to a marked increase in the number of astrocytes and microglia and a decrease in the number of neurons.These results indicate that 5-HT deficiency may play a role in the pathogenesis of amyotrophic lateral sclerosis by inducing the abnormal expression and/or distribution of TDP-43 and SOD1-G93A and by activating glial cells.5-HT co uld therefore be a potential therapeutic target for amyotrophic lateral sclerosis.
基金partially supported by the National Natural Science Foundation of China(Nos.81473120,81501536,81473120)
文摘This study aimed to seek necrosis avid agents with high safety from DNA binding agents.The interaction of 5-hydroxytryptophan(5-HTP)with DNA was investigated by a series of spectroscopic studies.Then,5-HTP was labeled with iodine-131([^(131)I]5-HTP)and the necrosis avidity of[^(131)I]5-HTP was evaluated by in vitro cell binding assays,in vivo biodistribution experiments and blocking experiment.Finally,the potential of[^(131)I]5-HTP to image necrotic myocardium was explored in rat models with myocardial infarction by SPECT/CT imaging.Results showed that 5-HTP bound to DNA in groove binding mode and the binding constant was 1.69×10~4 L/mol.[~(^(131))I]5-HTP showed specific affinity to necrotic A549 cells,which might be related to cell nucleus.Biodistribution and autoradiography results showed preferential accumulation of[^(131)I]5-HTP in necrotic muscle(necrotic/viable muscle ratio:6.95?0.68 at 3 h postinjection(p.i.)),which could be blocked by 5-HTP with 66.7%decline,indicating that[^(131)I]5-HTP might share the same necrotic targets with 5-HTP.On SPECT/CT images,a hotspot was clearly observed at 3h p.i.in the necrotic myocardium while not in the control myocardium.In conclusion,[^(131)I]5-HTP is a novel necrosis avid agent and can rapidly visualize necrotic myocardium at 3 h p.i.The necrosis avidity mechanism of[^(131)I]5-HTP may be attributed to its interactions with exposed DNA in the necrotic tissues.
基金Effect of 5-hydroxytryptamine Receptor in the Lower Esophageal Sphincter Regulation Mechanism(Number:18ZF23)。
文摘In the first and second parts of this study,5-hydroxytryptamine(5HT)receptors,including 5-HT3 and 5-HT4 with the highest expression level,were found in clasp and sling fibres of the lower esophageal sphincter(LES).Specific 5-HT3 and 5-HT4 receptor agonists can induce the contraction effect of clasp and sling fibres of the LES while specific 5-HT7 receptor agonists showed no effects.In the study of this part,the in-vitro muscle tension measurement technology and EFS methods were used to detect the effect of the selective 5-HT receptor antagonist on the clasp and sling fibres of the in-vitro LES under the electrical field stimulation(EFS),and further to ensure the effect of 5-HT receptor in the LES neuroregulatory pathway,and deeply explore the effect of 5-HT receptor in the systolic and diastolic function regulation of the LES.
基金supported by the Notional Natural Science Foundation of China,Nos.81371213 and 8107098 7the Natural Science Foundation of Shanghai,No.21ZR1468400 (all to QLY)。
文摘Extracellular amyloid beta(Aβ) plaques are main pathological feature of Alzheimer’s disease.However,the specific type of neuro ns that produce Aβ peptides in the initial stage of Alzheimer’s disease are unknown.In this study,we found that 5-hydroxytryptamin receptor 3A subunit(HTR3A) was highly expressed in the brain tissue of transgenic amyloid precursor protein and presenilin-1 mice(an Alzheimer’s disease model) and patients with Alzheimer’s disease.To investigate whether HTR3A-positive interneurons are associated with the production of Aβ plaques,we performed double immunostaining and found that HTR3A-positive interneurons were clustered around Aβ plaques in the mouse model.Some amyloid precursor protein-positive or β-site amyloid precursor protein cleaving enzyme-1-positive neurites near Aβ plaques were co-localized with HTR3A interneurons.These results suggest that HTR3A-positive interneurons may partially contribute to the generation of Aβ peptides.We treated 5.0-5.5-month-old model mice with tro pisetron,a HTR3 antagonist,for 8 consecutive weeks.We found that the cognitive deficit of mice was partially reversed,Aβ plaques and neuroinflammation we re remarkably reduced,the expression of HTR3 was remarkably decreased and the calcineurin/nuclear factor of activated T-cell 4 signaling pathway was inhibited in treated model mice.These findings suggest that HTR3A interneurons partly contribute to generation of Aβ peptide at the initial stage of Alzheimer’s disease and inhibiting HTR3 partly reve rses the pathological changes of Alzheimer’s disease.
基金Effect of 5-hydroxytryptamine Receptor in the Lower Esophageal Sphincter Regulation Mechanism(NO.18ZF23)。
文摘As a neurotransmitter and avascular active substance,the 5-hydroxytryptamine(5-HT,serotonin)is widely distributed in the central nervous system and surrounding tissues.The 5-HT can play its role by acting on its corresponding 5-HT receptor.Nowadays,the 5-HT receptor can be classified into seven,according to different signal transduction method of receptors,the 5-HT3 receptor belongs to the ligandgated ion channels,while other six 5-HT receptors are involved into the G protein-coupled receptors and play the biological role by binding to specific G protein-coupled receptors(GPCRs)on the surface of the cell membrane.The 5-HT plays an important role in the brain-gut information transmission and studies showed that the physiological stimulations like having meals,and pathological stimulations like ischemia and stress could promote the release of the 5-HT.In the gastrointestinal tract,the 5-HT is closely related to gastrointestinal sensitivity,gastrointestinal movement and secretion regulation,as well as many gastrointestinal dysfunction disorders,such as gastrointestinal power and visceral sensitivity abnormality and abnormalities of brain-gut axis.
