BACKGROUND The effects of prostaglandin E(PGE)combined with continuous renal replacement therapy(CRRT)on renal function and inflammatory responses in patients with septic acute kidney injury(SAKI)remain unclear.AIM To...BACKGROUND The effects of prostaglandin E(PGE)combined with continuous renal replacement therapy(CRRT)on renal function and inflammatory responses in patients with septic acute kidney injury(SAKI)remain unclear.AIM To investigate the effects of PGE combined with CRRT on urinary augmenter of liver regeneration(ALR),urinary Na+/H+exchanger 3(NHE3),and serum inflammatory cytokines in patients with SAKI.METHODS The clinical data of 114 patients with SAKI admitted to Yichang Second People's Hospital from May 2017 to January 2019 were collected.Fifty-three cases treated by CRRT alone were included in a control group,while the other 61 cases treated with PGE combined with CRRT were included in an experimental group.Their urinary ALR,urinary NHE3,serum inflammatory cytokines,renal function indices,and immune function indices were detected.Changes in disease recovery and the incidence of adverse reactions were observed.The 28-d survival curve was plotted.RESULTS Before treatment,urinary ALR,urinary NHE3,blood urea nitrogen(BUN),serum creatinine(SCr),CD3+T lymphocytes,CD4+T lymphocytes,and CD4+/CD8+T lymphocyte ratio in the control and experimental groups were approximately the same.After treatment,urinary ALR and NHE3 decreased,while BUN,SCr,CD3+T lymphocytes,CD4+T lymphocytes,and CD4+/CD8+T lymphocyte ratio increased in all subjects.Urinary ALR,urinary NHE3,BUN,and SCr in the experimental group were significantly lower than those in the control group,while CD3+T lymphocytes,CD4+T lymphocytes,and CD4+/CD8+T lymphocyte ratio were significantly higher than those in the control group(P<0.05).After treatment,the levels of tumor necrosis factor-α,interleukin-18,and high sensitivity C-reactive protein in the experimental group were significantly lower than those in the control group(P<0.05).The time for urine volume recovery and intensive care unit treatment in the experimental group was significantly shorter than that in the control group(P<0.05),although there was no statistically significant difference in hospital stays between the two groups.The total incidence of adverse reactions did not differ statistically between the two groups.The 28-d survival rate in the experimental group(80.33%)was significantly higher than that in the control group(66.04%).CONCLUSION PGE combined with CRRT is clinically effective for treating SAKI,and the combination therapy can significantly improve renal function and reduce inflammatory responses.展开更多
We determined whether La3+ enter human peripheral blood lymphocytes via Na+/Ca2+ exchanger (measured with fura-2). We first compared the sensitivity of fura-2 with La3+ and Ca2+, the result indicates that the sensitiv...We determined whether La3+ enter human peripheral blood lymphocytes via Na+/Ca2+ exchanger (measured with fura-2). We first compared the sensitivity of fura-2 with La3+ and Ca2+, the result indicates that the sensitivity of fura-2 for La3+ is much greater than for Ca2+. La3+ forms a 1:1 La3+-fura-2 complex (apparent dissociation constant = 1.7x10(-12) mol/L, pH 7.05). Ouabain-pretreated cells, suspended in Na+-free medium, showed that La3+ can enter human lymphocytes via the Na-i(+)/Ca2+ (La3+)(o) exchanger and is found to be about 10(-12) mol/L in cells exposed to 0.4 mmol/L La3+. Otherwise, the higher concentration (0.1 mmol/L) blocks the Na-i(+)/Ca2+(La3+)(o) exchange-mediated influx of Ca2+, but the lower concentration (0.01 mmol/L) appears to increase Ca2+ entry.展开更多
This paper reports the kinetic process of Ag ion exchange for the polycrystalline Na-β'-Al2O3.The interdiffusion coefficients in the process of Ag+ and Na+ ion exchange have been calculated with an 'one dimen...This paper reports the kinetic process of Ag ion exchange for the polycrystalline Na-β'-Al2O3.The interdiffusion coefficients in the process of Ag+ and Na+ ion exchange have been calculated with an 'one dimensional double side diffusion model'. Microstructures of the samples were observed and analysed by XRD, EMPA, SEM. The results of the conductivity measurements for samples with Na+, Ag+ and Na+-Ag+ mobile ions are presented and explained展开更多
To determine the effects of HOE 694, a new and potent Na＋- H＋ exchanger blocker, on transient inward current (Iti) and Na＋- Ca2＋ exchange during hypoxia- reoxygenation in guinea pig cardiomyocytes. Methods. Cardio...To determine the effects of HOE 694, a new and potent Na＋- H＋ exchanger blocker, on transient inward current (Iti) and Na＋- Ca2＋ exchange during hypoxia- reoxygenation in guinea pig cardiomyocytes. Methods. Cardiomyocytes were isolated from adult guinea pig ventricle. Experiment was performed in an experimental chamber that allowed the cells to be exposed to a sufficiently low O2 pressure. The cells were subjected to hypoxia and reoxygenation. The ionic currents were studied with patch clamp technique. Results. In the absence of HOE 694, hypoxia- reoxygenation induced Iti in 12 of 15 experiments; but in cardiomyocytes pretreated with HOE 694 (10～ 50μ mol/L), the incidence of Iti observed during reoxygenation was reduced to 5 of 11 experiments and 3 of 10 experiments, P Conclusions. Blockade of the Na＋- H＋ exchange by HOE 694 could reduce Ca2＋ overload upon hypoxia- reoxygenation, and inhibition of Na＋- H＋ exchange may also indirectly decrease Na＋- Ca2＋ exchange activity during hypoxia.展开更多
The liver has many significant functions,such as detoxification,the urea cycle,gluconeogenesis,and protein synthesis.Systemic diseases,hypoxia,infections,drugs,and toxins can easily affect the liver,which is extremely...The liver has many significant functions,such as detoxification,the urea cycle,gluconeogenesis,and protein synthesis.Systemic diseases,hypoxia,infections,drugs,and toxins can easily affect the liver,which is extremely sensitive to injury.Systemic infection of severe acute respiratory syndrome coronavirus 2 can cause liver damage.The primary regulator of intracellular pH in the liver is the Na+/H+exchanger(NHE).Physiologically,NHE protects hepatocytes from apoptosis by making the intracellular pH alkaline.Severe acute respiratory syndrome coronavirus 2 increases local angiotensin II levels by binding to angiotensinconverting enzyme 2.In severe cases of coronavirus disease 2019,high angiotensin II levels may cause NHE overstimulation and lipid accumulation in the liver.NHE overstimulation can lead to hepatocyte death.NHE overstimulation may trigger a cytokine storm by increasing proinflammatory cytokines in the liver.Since the release of proinflammatory cytokines such as interleukin-6 increases with NHE activation,the virus may indirectly cause an increase in fibrinogen and D-dimer levels.NHE overstimulation may cause thrombotic events and systemic damage by increasing fibrinogen levels and cytokine release.Also,NHE overstimulation causes an increase in the urea cycle while inhibiting vitamin D synthesis and gluconeogenesis in the liver.Increasing NHE3 activity leads to Na+loading,which impairs the containment and fluidity of bile acid.NHE overstimulation can change the gut microbiota composition by disrupting the structure and fluidity of bile acid,thus triggering systemic damage.Unlike other tissues,tumor necrosis factor-alpha and angiotensin II decrease NHE3 activity in the intestine.Thus,increased luminal Na+leads to diarrhea and cytokine release.Severe acute respiratory syndrome coronavirus 2-induced local and systemic damage can be improved by preventing virus-induced NHE overstimulation in the liver.展开更多
At present, there are relevant scientific materials on the cellular and molecular mechanisms of electrogenic Na/K pump function and structure, as well as on the potential- and ligand-activated ionic channels in the me...At present, there are relevant scientific materials on the cellular and molecular mechanisms of electrogenic Na/K pump function and structure, as well as on the potential- and ligand-activated ionic channels in the membrane. However, the role of electrogenic Na/K pump in regulation of semipermeable properties of cell membrane has not been elucidated yet, which is due to the fact that our knowledge about the biophysical properties of cell membrane is based on the conductive membrane theory of Hodgkin-Huxley-Katz, which is developed on internally perfused squid axon and lacks intracellular metabolism. Thus, the accumulated abundance of data on the role of G-proteins-dependent intracellular signaling system in regulation of Na/K pump activity and biophysical properties of cell membrane presumes fundamental revision of some statements of membrane theory. The aim of the present review is to briefly demonstrate our and literature data on cell hydration-induced auto-regulation of Na/K pump as well as on its role in metabolic control of semipermeable properties and excitability of neuronal membrane, which are omitted in the study of internally perfused squid axon.展开更多
This study aimed at the exploration of the relationship between Na+-H+ exchange system and myocardial ischemia-reperfusion injury(MRI)in an attempt to provide a theoretic basis for the prevention and treatment of MRI....This study aimed at the exploration of the relationship between Na+-H+ exchange system and myocardial ischemia-reperfusion injury(MRI)in an attempt to provide a theoretic basis for the prevention and treatment of MRI.We used the isolated working guinea pig hearts as the experimental model to mimick cardiopulmonary bypass,which included 120 min hypothermic ischemic cardioplegic arrest followed by 60 min normothermic reperfusion.The hearts were divided into 2 groups:the control group receiving St.Thomas'Hospital Solution(STS)and the treated group receiving STS+ amiloride,a Na+-H+ exchangeblocker.The results showed that during reperfusion,[Na+]i and [Ca2+]i overloads,poor recovery of cardiac function,increases in CPK release and OFR generation,reduction of ATP content and serious damage of ultrastructure were seen in group 1;whereas there were no [Na+]i and [Ca2+]i overloads and better recovery of cardiac function accompanied by improved results of biochemical assay and less damage of ultrastructure was found in group 2.Our study indicates that amiloride can inhibit Na+-H+ exchange system in cardiac cells during early reperfusion period,which prevents [Na+]i overload produced by Na+-H+ exchange,and stops Na+-Ca2+ exchange activated by high level of [Na+]i,thus attenuating [Ca2+]ioverload caused by Na+-Ca2+ exchange and myocardial injury.Therefore,we conclude that Na+-H+ exchange blocker,amiloride,can exert significant protective effects on MRI and its use may prove to be a new clinical approach to prevention and cure of MRI.展开更多
Background Recent studies showed the central Na＋/H＋ exchanger type 3 （NHE3） has a close relationship with ventilation control.The objective of the study is to investigate the role of NHE3 in sleep apnea in Sprague...Background Recent studies showed the central Na＋/H＋ exchanger type 3 （NHE3） has a close relationship with ventilation control.The objective of the study is to investigate the role of NHE3 in sleep apnea in Sprague-Dawley （SD） rats.Methods A sleep study was performed on 20 male SD rats to analyze the correlation between the sleep apneic events and total NHE3 protein content and inactive NHE3（pS552） in the brainstem measured by Western blotting.Another 20 adult male SD rats received 3 days of sleep and respiration monitoring for 6 hours a day,with adaption on the first day,0.5％ DMSO microinjection into the fourth ventricle on the second day,and AVE0657 （specific inhibitor of NHE3） microinjection on the third day.Rats were divided into two groups with injection of 5 μmol/L or 8 μmol/L AVE0657 before the sleep study.The effects of AVE0657 on sleep apnea and sleep structure of rats were analyzed through self-control.Results The total post-sigh apnea index （TPSAI） and post-sigh apnea index in non-rapid eye movement （NREM） sleep （NPSAI） and total apnea index （AI） in NREM sleep （NAI） were negatively correlated with NHE3（pS552） protein contents in the brainstem （r=-0.534,-0.547 and-0.505,respectively,P＜0.05）.The spontaneous apnea index in REM sleep （RSPAI） was positively correlated with the level of NHE3（pS552） protein expression in the brainstem （r=0.556,P＜0.05）.However,the sleep AI had no relationship with total NHE3 protein.Compared with the blank control and microinjection of 0.5％ DMSO,5 μmol/L AVE0657 significantly reduced the total AI and NPSAI （both P＜0.05） without a significant effect on sleep architecture.In contrast to blank control and microinjection of 0.5％ DMSO,injection of 8 μmol/L AVE0657 significantly reduced the AI and PSAI in NREM and REM sleep （all P＜0.05）.Conclusions The severity of sleep apnea was negatively correlated with central inactive NHE3.A specific inhibitor of NHE3 decreased the sleep AI.Thus,our results indicate that central NHE3 might be a molecular target for sleep apnea treatment,whose inhibitors may be potential therapeutic drugs for sleep apnea.展开更多
Objective To study the alteration of Na + Ca 2+ exchange in rat cardiac sarcolemmal membrane during phases of septic shock Methods Sepsis was induced by cecal ligation and puncture (CLP) Na + Ca 2+ ...Objective To study the alteration of Na + Ca 2+ exchange in rat cardiac sarcolemmal membrane during phases of septic shock Methods Sepsis was induced by cecal ligation and puncture (CLP) Na + Ca 2+ exchange was assayed by radioactive analysis Results Na + dependent 45 Ca 2+ uptake was decreased by 62%-69% in late phase of sepsis, whereas it was not affected in early phase of sepsis Na + Ca 2+ exchange stimulated by 5'guanylyl imidodiphosphate [Gpp(NH)p] was decreased by 65 7% in late phase of sepsis but unaltered in early phase of sepsis Two agonists (angiotensin Ⅱ and phenylephrine) coupled to Gq and a protein kinase C activator, phorbol 12 myristate 13 acetate (PMA) all inhibited Na + Ca 2+ exchange in late phase of sepsis Na + Ca 2+ exchange activities induced by phosphorylation of Na + Ca 2+ exchange were decreased in late phase of sepsis, whereas inhibition of Na + Ca 2+ exchange by dephosphorylation was increased both in early and late phases of sepsis Conclusion The alteration of Na + Ca 2+ exchange during different phases of sepsis might be related to the activities of Gq, protein kinase C, and phosphorylation/dephosphorylation展开更多
文摘BACKGROUND The effects of prostaglandin E(PGE)combined with continuous renal replacement therapy(CRRT)on renal function and inflammatory responses in patients with septic acute kidney injury(SAKI)remain unclear.AIM To investigate the effects of PGE combined with CRRT on urinary augmenter of liver regeneration(ALR),urinary Na+/H+exchanger 3(NHE3),and serum inflammatory cytokines in patients with SAKI.METHODS The clinical data of 114 patients with SAKI admitted to Yichang Second People's Hospital from May 2017 to January 2019 were collected.Fifty-three cases treated by CRRT alone were included in a control group,while the other 61 cases treated with PGE combined with CRRT were included in an experimental group.Their urinary ALR,urinary NHE3,serum inflammatory cytokines,renal function indices,and immune function indices were detected.Changes in disease recovery and the incidence of adverse reactions were observed.The 28-d survival curve was plotted.RESULTS Before treatment,urinary ALR,urinary NHE3,blood urea nitrogen(BUN),serum creatinine(SCr),CD3+T lymphocytes,CD4+T lymphocytes,and CD4+/CD8+T lymphocyte ratio in the control and experimental groups were approximately the same.After treatment,urinary ALR and NHE3 decreased,while BUN,SCr,CD3+T lymphocytes,CD4+T lymphocytes,and CD4+/CD8+T lymphocyte ratio increased in all subjects.Urinary ALR,urinary NHE3,BUN,and SCr in the experimental group were significantly lower than those in the control group,while CD3+T lymphocytes,CD4+T lymphocytes,and CD4+/CD8+T lymphocyte ratio were significantly higher than those in the control group(P<0.05).After treatment,the levels of tumor necrosis factor-α,interleukin-18,and high sensitivity C-reactive protein in the experimental group were significantly lower than those in the control group(P<0.05).The time for urine volume recovery and intensive care unit treatment in the experimental group was significantly shorter than that in the control group(P<0.05),although there was no statistically significant difference in hospital stays between the two groups.The total incidence of adverse reactions did not differ statistically between the two groups.The 28-d survival rate in the experimental group(80.33%)was significantly higher than that in the control group(66.04%).CONCLUSION PGE combined with CRRT is clinically effective for treating SAKI,and the combination therapy can significantly improve renal function and reduce inflammatory responses.
基金The authors acknowledge the support of the National Natural Scicnce Foundation of ChinaProvincial Natural Science Foundation of Shanxi.
文摘We determined whether La3+ enter human peripheral blood lymphocytes via Na+/Ca2+ exchanger (measured with fura-2). We first compared the sensitivity of fura-2 with La3+ and Ca2+, the result indicates that the sensitivity of fura-2 for La3+ is much greater than for Ca2+. La3+ forms a 1:1 La3+-fura-2 complex (apparent dissociation constant = 1.7x10(-12) mol/L, pH 7.05). Ouabain-pretreated cells, suspended in Na+-free medium, showed that La3+ can enter human lymphocytes via the Na-i(+)/Ca2+ (La3+)(o) exchanger and is found to be about 10(-12) mol/L in cells exposed to 0.4 mmol/L La3+. Otherwise, the higher concentration (0.1 mmol/L) blocks the Na-i(+)/Ca2+(La3+)(o) exchange-mediated influx of Ca2+, but the lower concentration (0.01 mmol/L) appears to increase Ca2+ entry.
文摘This paper reports the kinetic process of Ag ion exchange for the polycrystalline Na-β'-Al2O3.The interdiffusion coefficients in the process of Ag+ and Na+ ion exchange have been calculated with an 'one dimensional double side diffusion model'. Microstructures of the samples were observed and analysed by XRD, EMPA, SEM. The results of the conductivity measurements for samples with Na+, Ag+ and Na+-Ag+ mobile ions are presented and explained
基金This work was supported by Leading Specialty Funding of Shanghai, Grant No.94- III- 001.
文摘To determine the effects of HOE 694, a new and potent Na＋- H＋ exchanger blocker, on transient inward current (Iti) and Na＋- Ca2＋ exchange during hypoxia- reoxygenation in guinea pig cardiomyocytes. Methods. Cardiomyocytes were isolated from adult guinea pig ventricle. Experiment was performed in an experimental chamber that allowed the cells to be exposed to a sufficiently low O2 pressure. The cells were subjected to hypoxia and reoxygenation. The ionic currents were studied with patch clamp technique. Results. In the absence of HOE 694, hypoxia- reoxygenation induced Iti in 12 of 15 experiments; but in cardiomyocytes pretreated with HOE 694 (10～ 50μ mol/L), the incidence of Iti observed during reoxygenation was reduced to 5 of 11 experiments and 3 of 10 experiments, P Conclusions. Blockade of the Na＋- H＋ exchange by HOE 694 could reduce Ca2＋ overload upon hypoxia- reoxygenation, and inhibition of Na＋- H＋ exchange may also indirectly decrease Na＋- Ca2＋ exchange activity during hypoxia.
文摘The liver has many significant functions,such as detoxification,the urea cycle,gluconeogenesis,and protein synthesis.Systemic diseases,hypoxia,infections,drugs,and toxins can easily affect the liver,which is extremely sensitive to injury.Systemic infection of severe acute respiratory syndrome coronavirus 2 can cause liver damage.The primary regulator of intracellular pH in the liver is the Na+/H+exchanger(NHE).Physiologically,NHE protects hepatocytes from apoptosis by making the intracellular pH alkaline.Severe acute respiratory syndrome coronavirus 2 increases local angiotensin II levels by binding to angiotensinconverting enzyme 2.In severe cases of coronavirus disease 2019,high angiotensin II levels may cause NHE overstimulation and lipid accumulation in the liver.NHE overstimulation can lead to hepatocyte death.NHE overstimulation may trigger a cytokine storm by increasing proinflammatory cytokines in the liver.Since the release of proinflammatory cytokines such as interleukin-6 increases with NHE activation,the virus may indirectly cause an increase in fibrinogen and D-dimer levels.NHE overstimulation may cause thrombotic events and systemic damage by increasing fibrinogen levels and cytokine release.Also,NHE overstimulation causes an increase in the urea cycle while inhibiting vitamin D synthesis and gluconeogenesis in the liver.Increasing NHE3 activity leads to Na+loading,which impairs the containment and fluidity of bile acid.NHE overstimulation can change the gut microbiota composition by disrupting the structure and fluidity of bile acid,thus triggering systemic damage.Unlike other tissues,tumor necrosis factor-alpha and angiotensin II decrease NHE3 activity in the intestine.Thus,increased luminal Na+leads to diarrhea and cytokine release.Severe acute respiratory syndrome coronavirus 2-induced local and systemic damage can be improved by preventing virus-induced NHE overstimulation in the liver.
文摘At present, there are relevant scientific materials on the cellular and molecular mechanisms of electrogenic Na/K pump function and structure, as well as on the potential- and ligand-activated ionic channels in the membrane. However, the role of electrogenic Na/K pump in regulation of semipermeable properties of cell membrane has not been elucidated yet, which is due to the fact that our knowledge about the biophysical properties of cell membrane is based on the conductive membrane theory of Hodgkin-Huxley-Katz, which is developed on internally perfused squid axon and lacks intracellular metabolism. Thus, the accumulated abundance of data on the role of G-proteins-dependent intracellular signaling system in regulation of Na/K pump activity and biophysical properties of cell membrane presumes fundamental revision of some statements of membrane theory. The aim of the present review is to briefly demonstrate our and literature data on cell hydration-induced auto-regulation of Na/K pump as well as on its role in metabolic control of semipermeable properties and excitability of neuronal membrane, which are omitted in the study of internally perfused squid axon.
文摘This study aimed at the exploration of the relationship between Na+-H+ exchange system and myocardial ischemia-reperfusion injury(MRI)in an attempt to provide a theoretic basis for the prevention and treatment of MRI.We used the isolated working guinea pig hearts as the experimental model to mimick cardiopulmonary bypass,which included 120 min hypothermic ischemic cardioplegic arrest followed by 60 min normothermic reperfusion.The hearts were divided into 2 groups:the control group receiving St.Thomas'Hospital Solution(STS)and the treated group receiving STS+ amiloride,a Na+-H+ exchangeblocker.The results showed that during reperfusion,[Na+]i and [Ca2+]i overloads,poor recovery of cardiac function,increases in CPK release and OFR generation,reduction of ATP content and serious damage of ultrastructure were seen in group 1;whereas there were no [Na+]i and [Ca2+]i overloads and better recovery of cardiac function accompanied by improved results of biochemical assay and less damage of ultrastructure was found in group 2.Our study indicates that amiloride can inhibit Na+-H+ exchange system in cardiac cells during early reperfusion period,which prevents [Na+]i overload produced by Na+-H+ exchange,and stops Na+-Ca2+ exchange activated by high level of [Na+]i,thus attenuating [Ca2+]ioverload caused by Na+-Ca2+ exchange and myocardial injury.Therefore,we conclude that Na+-H+ exchange blocker,amiloride,can exert significant protective effects on MRI and its use may prove to be a new clinical approach to prevention and cure of MRI.
基金This work was supported bygrants from the National Natural Science Foundation of China （No. 30900646） and the National Science Foundation of China （No. 81241004）. Conflict of interest： None.
文摘Background Recent studies showed the central Na＋/H＋ exchanger type 3 （NHE3） has a close relationship with ventilation control.The objective of the study is to investigate the role of NHE3 in sleep apnea in Sprague-Dawley （SD） rats.Methods A sleep study was performed on 20 male SD rats to analyze the correlation between the sleep apneic events and total NHE3 protein content and inactive NHE3（pS552） in the brainstem measured by Western blotting.Another 20 adult male SD rats received 3 days of sleep and respiration monitoring for 6 hours a day,with adaption on the first day,0.5％ DMSO microinjection into the fourth ventricle on the second day,and AVE0657 （specific inhibitor of NHE3） microinjection on the third day.Rats were divided into two groups with injection of 5 μmol/L or 8 μmol/L AVE0657 before the sleep study.The effects of AVE0657 on sleep apnea and sleep structure of rats were analyzed through self-control.Results The total post-sigh apnea index （TPSAI） and post-sigh apnea index in non-rapid eye movement （NREM） sleep （NPSAI） and total apnea index （AI） in NREM sleep （NAI） were negatively correlated with NHE3（pS552） protein contents in the brainstem （r=-0.534,-0.547 and-0.505,respectively,P＜0.05）.The spontaneous apnea index in REM sleep （RSPAI） was positively correlated with the level of NHE3（pS552） protein expression in the brainstem （r=0.556,P＜0.05）.However,the sleep AI had no relationship with total NHE3 protein.Compared with the blank control and microinjection of 0.5％ DMSO,5 μmol/L AVE0657 significantly reduced the total AI and NPSAI （both P＜0.05） without a significant effect on sleep architecture.In contrast to blank control and microinjection of 0.5％ DMSO,injection of 8 μmol/L AVE0657 significantly reduced the AI and PSAI in NREM and REM sleep （all P＜0.05）.Conclusions The severity of sleep apnea was negatively correlated with central inactive NHE3.A specific inhibitor of NHE3 decreased the sleep AI.Thus,our results indicate that central NHE3 might be a molecular target for sleep apnea treatment,whose inhibitors may be potential therapeutic drugs for sleep apnea.
文摘Objective To study the alteration of Na + Ca 2+ exchange in rat cardiac sarcolemmal membrane during phases of septic shock Methods Sepsis was induced by cecal ligation and puncture (CLP) Na + Ca 2+ exchange was assayed by radioactive analysis Results Na + dependent 45 Ca 2+ uptake was decreased by 62%-69% in late phase of sepsis, whereas it was not affected in early phase of sepsis Na + Ca 2+ exchange stimulated by 5'guanylyl imidodiphosphate [Gpp(NH)p] was decreased by 65 7% in late phase of sepsis but unaltered in early phase of sepsis Two agonists (angiotensin Ⅱ and phenylephrine) coupled to Gq and a protein kinase C activator, phorbol 12 myristate 13 acetate (PMA) all inhibited Na + Ca 2+ exchange in late phase of sepsis Na + Ca 2+ exchange activities induced by phosphorylation of Na + Ca 2+ exchange were decreased in late phase of sepsis, whereas inhibition of Na + Ca 2+ exchange by dephosphorylation was increased both in early and late phases of sepsis Conclusion The alteration of Na + Ca 2+ exchange during different phases of sepsis might be related to the activities of Gq, protein kinase C, and phosphorylation/dephosphorylation
