Dysregulation of hyperpolarization-activated cyclic nucleotide-gated cation(HCN)channels alters neuronal excitability.However,the role of HCN channels in status epilepticus is not fully understood.In this study,we est...Dysregulation of hyperpolarization-activated cyclic nucleotide-gated cation(HCN)channels alters neuronal excitability.However,the role of HCN channels in status epilepticus is not fully understood.In this study,we established rat models of pentylenetetrazole-induced status epilepticus.We performed western blot assays and immunofluorescence staining.Our results showed that HCN1 channel protein expression,particularly HCN1 surface protein,was significantly decreased in the hippocampal CA1 region,whereas the expression of HCN2 channel protein was unchanged.Moreover,metabolic glutamate receptor 1(mGluR1)protein expression was increased after status epilepticus.The mGluR1 agonist(RS)-3,5-dihydroxyphenylglycine injected intracerebroventricularly increased the sensitivity and severity of pentylenetetrazole-induced status epilepticus,whereas application of the mGluR1 antagonist(+)-2-methyl-4-carboxyphenylglycine(LY367385)alleviated the severity of pentylenetetrazole-induced status epilepticus.The results from double immunofluorescence labeling revealed that mGluR1 and HCN1 were co-localized in the CA1 region.Subsequently,a protein kinase A inhibitor(H89)administered intraperitoneally successfully reversed HCN1 channel inhibition,thereby suppressing the severity and prolonging the latency of pentylenetetrazole-induced status epilepticus.Furthermore,H89 reduced the level of mGluR1,downregulated cyclic adenosine monophosphate(cAMP)/protein kinase A expression,significantly increased tetratricopeptide repeat-containing Rab8b-interacting protein(TRIP8b)(1a-4)expression,and restored TRIP8b(1b-2)levels.TRIP8b(1a-4)and TRIP8b(1b-2)are subunits of Rab8b interacting protein that regulate HCN1 surface protein.展开更多
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
基金supported by the National Natural Science Foundation of China,No.81760242(to MGM).
文摘Dysregulation of hyperpolarization-activated cyclic nucleotide-gated cation(HCN)channels alters neuronal excitability.However,the role of HCN channels in status epilepticus is not fully understood.In this study,we established rat models of pentylenetetrazole-induced status epilepticus.We performed western blot assays and immunofluorescence staining.Our results showed that HCN1 channel protein expression,particularly HCN1 surface protein,was significantly decreased in the hippocampal CA1 region,whereas the expression of HCN2 channel protein was unchanged.Moreover,metabolic glutamate receptor 1(mGluR1)protein expression was increased after status epilepticus.The mGluR1 agonist(RS)-3,5-dihydroxyphenylglycine injected intracerebroventricularly increased the sensitivity and severity of pentylenetetrazole-induced status epilepticus,whereas application of the mGluR1 antagonist(+)-2-methyl-4-carboxyphenylglycine(LY367385)alleviated the severity of pentylenetetrazole-induced status epilepticus.The results from double immunofluorescence labeling revealed that mGluR1 and HCN1 were co-localized in the CA1 region.Subsequently,a protein kinase A inhibitor(H89)administered intraperitoneally successfully reversed HCN1 channel inhibition,thereby suppressing the severity and prolonging the latency of pentylenetetrazole-induced status epilepticus.Furthermore,H89 reduced the level of mGluR1,downregulated cyclic adenosine monophosphate(cAMP)/protein kinase A expression,significantly increased tetratricopeptide repeat-containing Rab8b-interacting protein(TRIP8b)(1a-4)expression,and restored TRIP8b(1b-2)levels.TRIP8b(1a-4)and TRIP8b(1b-2)are subunits of Rab8b interacting protein that regulate HCN1 surface protein.
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。
