目的:观察HCN1,HCN2在功能性便秘(function constipation,FC)大鼠模型结肠上的表达及其与结肠Cajal间质细胞(interstitial cells of Cajal,ICCs)细胞之间的关系,探讨HCN1,HCN2对FC发病的影响。方法:用复方地芬诺酯制造FC大鼠模型,利用...目的:观察HCN1,HCN2在功能性便秘(function constipation,FC)大鼠模型结肠上的表达及其与结肠Cajal间质细胞(interstitial cells of Cajal,ICCs)细胞之间的关系,探讨HCN1,HCN2对FC发病的影响。方法:用复方地芬诺酯制造FC大鼠模型,利用免疫组织化学分别对模型组(n=12)、空白组(n=12)大鼠升结肠、横结肠、降结肠黏膜HCN1,HCN2及ICC的表达情况进行检测。结果:模型组和空白组升结肠、横结肠及降结肠均见HCN1,HCN2,c-Kit表达,模型组中HCN1,HCN2,c-Kit表达量明显低于空白组(P<0.05);HCN1表达在FC大鼠结肠中主要分布在结肠环形肌和纵行肌之间的肌ICC-MY,与c-Kit表达分布基本一致;HCN2在FC大鼠升结肠、横结肠及降结肠均有分布与c-Kit荧光度变化趋势基本一致。HCN2阳性神经元与ICCs的突起距离较近,二者未见细胞共存现象。结论:HCN通道作为一种与自主起博活动密切相关的离子通道,可能参与结肠ICCs的自主起博活动。HCN1,HCN2可能参与结肠运动调控,其数量、功能及分布异常可能与FC发病机制有关。展开更多
目的通过风湿性心脏病(简称风心病)心房颤动(简称房颤)患者右心耳组织超极化激活环核苷酸门控阳离子通道-2(HCN2)基因mRNA表达检测,探讨其与房颤的可能关系。方法 28例风心病患者根据是否存在房颤,分为房颤组和窦性心律(简称窦律)组,术...目的通过风湿性心脏病(简称风心病)心房颤动(简称房颤)患者右心耳组织超极化激活环核苷酸门控阳离子通道-2(HCN2)基因mRNA表达检测,探讨其与房颤的可能关系。方法 28例风心病患者根据是否存在房颤,分为房颤组和窦性心律(简称窦律)组,术前均行心脏彩色多普勒超声检测,术中取右心耳组织,应用半定量聚合酶链式反应技术检测HCN2mRNA表达。结果房颤组右房径大于窦律组((59.2±10.9 mm vs 41.7±15.5mm,P<0.05);HCN2mRNA表达水平高于窦律组(0.911 9±0.7052 vs 0.4735±0.3909,P<0.05)。结论HCN2mRNA表达异常增高,可能与风心病房颤的发生相关。展开更多
In the central nervous system,hyperpolarizationactivated cyclic nucleotide-gated(HCN)channels are essential to maintain normal neuronal function.Recent studies have shown that HCN channels may be involved in the patho...In the central nervous system,hyperpolarizationactivated cyclic nucleotide-gated(HCN)channels are essential to maintain normal neuronal function.Recent studies have shown that HCN channels may be involved in the pathological process of ischemic brain injury,but the mechanisms remain unclear.Autophagy is activated in cerebral ischemia,but its role in cell death/survival remains controversial.In this study,our results showed that the HCN channel blocker ZD7288 remarkably decreased the percentage of apoptotic neurons and corrected the excessive autophagy induced by oxygen-glucose deprivation followed by reperfusion(OGD/R)in hippocampal HT22 neurons.Furthermore,in the OGD/R group,p-mTOR,p-ULK1(Ser757),and p62 were significantly decreased,while p-ULK1(Ser317),atg5,and beclin1 were remarkably increased.ZD7288 did not change the expression of p-ULK1(Ser757),ULK1(Ser317),p62,Beclin1,and atg5,which are involved in regulating autophagosome formation.Besides,we found that OGD/R induced a significant increase in Cathepsin D expression,but not LAMP-1.Treatment with ZD7288 at 10μmol/L in the OGD/R group did not change the expression of cathepsin D and LAMP-1.However,chloroquine(CQ),which decreases autophagosome-lysosome fusion,eliminated the correction of excessive autophagy and neuroprotection by ZD7288.Besides,shRNA knockdown of HCN2 channels significantly reduced the accumulation of LC3-Ⅱand increased neuron survival in the OGD/R and transient global cerebral ischemia(TGCI)models,and CQ also eliminated the effects of HCN2-shRNA.Furthermore,we found that the percentage of LC3-positive puncta that co-localized with LAMP-1-positive lysosomes decreased in Con-shRNAtransfected HT22 neurons exposed to OGD/R or CQ.In HCN2-shRNA-transfected HT22 neurons,the percentage of LC3-positive puncta that co-localized with LAMP-1-positive lysosomes increased under OGD/R;however,the percentage was significantly decreased by the addition of CQ to HCN2-shRNA-transfected HT22 neurons.The present results demonstrated that blockade of HCN2 channels provides neuroprotection against OGD/R and TGCI by accelerating autophagic degradation attributable to the promotion of autophagosome and lysosome fusion.展开更多
The thalamocortical(TC)circuit is closely asso-ciated with pain processing.The hyperpolarization-activated cyclic nucleotide-gated(HCN)2 channel is predominantly expressed in the ventral posterolateral thalamus(VPL)th...The thalamocortical(TC)circuit is closely asso-ciated with pain processing.The hyperpolarization-activated cyclic nucleotide-gated(HCN)2 channel is predominantly expressed in the ventral posterolateral thalamus(VPL)that has been shown to mediate neuropathic pain.However,the role of VPL HCN2 in modulating TC circuit activity is largely unknown.Here,by using optogenetics,neuronal trac-ing,electrophysiological recordings,and virus knockdown strategies,we showed that the activation of VPL TC neurons potentiates excitatory synaptic transmission to the hindlimb region of the primary somatosensory cortex(S1HL)as well as mechanical hypersensitivity following spared nerve injury(SNI)-induced neuropathic pain in mice.Either pharmaco-logical blockade or virus knockdown of HCN2(shRNA-Hcn2)in the VPL was sufficient to alleviate SNI-induced hyperalgesia.Moreover,shRNA-Hcn2 decreased the excitability of TC neurons and synaptic transmission of the VPL-S1HL circuit.Together,our studies provide a novel mechanism by which HCN2 enhances the excitability of the TC circuit to facilitate neuropathic pain.展开更多
Aim To investigate whether tluoxetine, a selective serotonin reuptake inhibitor( SSRI) , could amelio- rate cognitive impairments induced by chronic cerebral hypopeffusion in rats and to clarify the underlying mecha...Aim To investigate whether tluoxetine, a selective serotonin reuptake inhibitor( SSRI) , could amelio- rate cognitive impairments induced by chronic cerebral hypopeffusion in rats and to clarify the underlying mecha- nisms of its efficacy. Methods Rats were subjected to permanent bilateral occlusion of the common carotid arteries (two-vessel occlusion, 2VO). Two weeks later, rats were treated with 30 mg · kg^-1 fluoxetine (intragastric injec- tion, i. g. ) for 6 weeks. Cognitive function was evaluated by Morris water maze (MWM) and novel objects recog- nition (NOR) test. Long-term potentiation (LTP) was used to address the underlying synaptic mechanisms. West- ern blot was used to quantify the protein levels. Results Fluoxetine treatment significantly improved the cognitive 2VO impairments caused by 2VO, accompanied with a reversion of 2VO-induced inhibitory of LTP. Furthermore, caused an up-regulation of hyperpolarization-activated cyclic nueleotide-gated channel 2 (HCN2) surface expres- sions in the hippocampal CA1 area and fluoxetine also effectively recovered the up-regulation of HCN2 surface ex- pressions. Conclusion Fluoxetine can ameliorate cognitive impairments induced by chronic cerebral hypopeffusion and a possible mechanism may via down-regulating HCN2 surface expression in the Hippocampal CA1 area.展开更多
文摘目的:观察HCN1,HCN2在功能性便秘(function constipation,FC)大鼠模型结肠上的表达及其与结肠Cajal间质细胞(interstitial cells of Cajal,ICCs)细胞之间的关系,探讨HCN1,HCN2对FC发病的影响。方法:用复方地芬诺酯制造FC大鼠模型,利用免疫组织化学分别对模型组(n=12)、空白组(n=12)大鼠升结肠、横结肠、降结肠黏膜HCN1,HCN2及ICC的表达情况进行检测。结果:模型组和空白组升结肠、横结肠及降结肠均见HCN1,HCN2,c-Kit表达,模型组中HCN1,HCN2,c-Kit表达量明显低于空白组(P<0.05);HCN1表达在FC大鼠结肠中主要分布在结肠环形肌和纵行肌之间的肌ICC-MY,与c-Kit表达分布基本一致;HCN2在FC大鼠升结肠、横结肠及降结肠均有分布与c-Kit荧光度变化趋势基本一致。HCN2阳性神经元与ICCs的突起距离较近,二者未见细胞共存现象。结论:HCN通道作为一种与自主起博活动密切相关的离子通道,可能参与结肠ICCs的自主起博活动。HCN1,HCN2可能参与结肠运动调控,其数量、功能及分布异常可能与FC发病机制有关。
文摘目的通过风湿性心脏病(简称风心病)心房颤动(简称房颤)患者右心耳组织超极化激活环核苷酸门控阳离子通道-2(HCN2)基因mRNA表达检测,探讨其与房颤的可能关系。方法 28例风心病患者根据是否存在房颤,分为房颤组和窦性心律(简称窦律)组,术前均行心脏彩色多普勒超声检测,术中取右心耳组织,应用半定量聚合酶链式反应技术检测HCN2mRNA表达。结果房颤组右房径大于窦律组((59.2±10.9 mm vs 41.7±15.5mm,P<0.05);HCN2mRNA表达水平高于窦律组(0.911 9±0.7052 vs 0.4735±0.3909,P<0.05)。结论HCN2mRNA表达异常增高,可能与风心病房颤的发生相关。
基金supported by grants from the National Natural Science Foundation of China (85100929)the Natural Science Foundation of Hubei Province,China (2018CFB302 and 2019CFB446)the Youth Fund of Health and Family Planning Commission of Wuhan Municipality,Hubei Province,China (WX18Q13 and WX18Q22)。
文摘In the central nervous system,hyperpolarizationactivated cyclic nucleotide-gated(HCN)channels are essential to maintain normal neuronal function.Recent studies have shown that HCN channels may be involved in the pathological process of ischemic brain injury,but the mechanisms remain unclear.Autophagy is activated in cerebral ischemia,but its role in cell death/survival remains controversial.In this study,our results showed that the HCN channel blocker ZD7288 remarkably decreased the percentage of apoptotic neurons and corrected the excessive autophagy induced by oxygen-glucose deprivation followed by reperfusion(OGD/R)in hippocampal HT22 neurons.Furthermore,in the OGD/R group,p-mTOR,p-ULK1(Ser757),and p62 were significantly decreased,while p-ULK1(Ser317),atg5,and beclin1 were remarkably increased.ZD7288 did not change the expression of p-ULK1(Ser757),ULK1(Ser317),p62,Beclin1,and atg5,which are involved in regulating autophagosome formation.Besides,we found that OGD/R induced a significant increase in Cathepsin D expression,but not LAMP-1.Treatment with ZD7288 at 10μmol/L in the OGD/R group did not change the expression of cathepsin D and LAMP-1.However,chloroquine(CQ),which decreases autophagosome-lysosome fusion,eliminated the correction of excessive autophagy and neuroprotection by ZD7288.Besides,shRNA knockdown of HCN2 channels significantly reduced the accumulation of LC3-Ⅱand increased neuron survival in the OGD/R and transient global cerebral ischemia(TGCI)models,and CQ also eliminated the effects of HCN2-shRNA.Furthermore,we found that the percentage of LC3-positive puncta that co-localized with LAMP-1-positive lysosomes decreased in Con-shRNAtransfected HT22 neurons exposed to OGD/R or CQ.In HCN2-shRNA-transfected HT22 neurons,the percentage of LC3-positive puncta that co-localized with LAMP-1-positive lysosomes increased under OGD/R;however,the percentage was significantly decreased by the addition of CQ to HCN2-shRNA-transfected HT22 neurons.The present results demonstrated that blockade of HCN2 channels provides neuroprotection against OGD/R and TGCI by accelerating autophagic degradation attributable to the promotion of autophagosome and lysosome fusion.
基金This work was supported by the National Natural Science Foundation of China(81960216,81903595,81860216,and 32060186)and the Natural Science Foundation of Jiangxi Province(20202BABL206049 and 20202BAB216043).
文摘The thalamocortical(TC)circuit is closely asso-ciated with pain processing.The hyperpolarization-activated cyclic nucleotide-gated(HCN)2 channel is predominantly expressed in the ventral posterolateral thalamus(VPL)that has been shown to mediate neuropathic pain.However,the role of VPL HCN2 in modulating TC circuit activity is largely unknown.Here,by using optogenetics,neuronal trac-ing,electrophysiological recordings,and virus knockdown strategies,we showed that the activation of VPL TC neurons potentiates excitatory synaptic transmission to the hindlimb region of the primary somatosensory cortex(S1HL)as well as mechanical hypersensitivity following spared nerve injury(SNI)-induced neuropathic pain in mice.Either pharmaco-logical blockade or virus knockdown of HCN2(shRNA-Hcn2)in the VPL was sufficient to alleviate SNI-induced hyperalgesia.Moreover,shRNA-Hcn2 decreased the excitability of TC neurons and synaptic transmission of the VPL-S1HL circuit.Together,our studies provide a novel mechanism by which HCN2 enhances the excitability of the TC circuit to facilitate neuropathic pain.
文摘Aim To investigate whether tluoxetine, a selective serotonin reuptake inhibitor( SSRI) , could amelio- rate cognitive impairments induced by chronic cerebral hypopeffusion in rats and to clarify the underlying mecha- nisms of its efficacy. Methods Rats were subjected to permanent bilateral occlusion of the common carotid arteries (two-vessel occlusion, 2VO). Two weeks later, rats were treated with 30 mg · kg^-1 fluoxetine (intragastric injec- tion, i. g. ) for 6 weeks. Cognitive function was evaluated by Morris water maze (MWM) and novel objects recog- nition (NOR) test. Long-term potentiation (LTP) was used to address the underlying synaptic mechanisms. West- ern blot was used to quantify the protein levels. Results Fluoxetine treatment significantly improved the cognitive 2VO impairments caused by 2VO, accompanied with a reversion of 2VO-induced inhibitory of LTP. Furthermore, caused an up-regulation of hyperpolarization-activated cyclic nueleotide-gated channel 2 (HCN2) surface expres- sions in the hippocampal CA1 area and fluoxetine also effectively recovered the up-regulation of HCN2 surface ex- pressions. Conclusion Fluoxetine can ameliorate cognitive impairments induced by chronic cerebral hypopeffusion and a possible mechanism may via down-regulating HCN2 surface expression in the Hippocampal CA1 area.