目的:了解糖尿病大鼠胃肠动力障碍时,回肠肌间神经丛有无形态学异常,以及第Ⅰ组代谢型谷氨酸受体mGluR1、mGluR5的表达变化,探讨谷氨酸能神经在糖尿病胃肠病变发生中的作用.方法:40只大鼠随机分为糖尿病组和对照组,给与高脂饮食结合腹...目的:了解糖尿病大鼠胃肠动力障碍时,回肠肌间神经丛有无形态学异常,以及第Ⅰ组代谢型谷氨酸受体mGluR1、mGluR5的表达变化,探讨谷氨酸能神经在糖尿病胃肠病变发生中的作用.方法:40只大鼠随机分为糖尿病组和对照组,给与高脂饮食结合腹腔注射STZ 30 mg/kg造糖尿病模型.运用肌间神经丛铺片观察谷氨酸能神经的分布及形态特征,并对其神经节和神经元进行定量研究,以及运用免疫荧光染色和RT-PCR方法观察大鼠回肠肠神经系统肌间神经丛的代谢型谷氨酸受体mGluR1、mGluR5的表达变化.结果:糖尿病大鼠肠神经系统肌间神经丛的谷氨酸能神经节和神经元的数目较对照组明显减少(mGluR1:4.5±3.1 vs 7.3±2.4;142.25±28.24vs 175.34±34.83,均P<0.05;mGluR5:4.3±2.1 vs 7.9±2.8,133.37±35.73 vs 168.34±32.66,均P<0.05),荧光强度较对照组减弱(mGluR1:145.23±28.78 vs 167.72±30.56,均P<0.05;mGluR5:141.54±18.46 vs 172.53±29.74,均P<0.05),mGluR1、mGluR5受体mRNA表达减少(1.05±0.27 vs 1.43±0.47,0.95±0.30vs 1.60±0.39,均P<0.01).结论:糖尿病大鼠回肠肠壁的肌间神经丛的神经节和神经元数目减少,以及兴奋性递质受体mGluR1、mGluR5的表达减少是导致胃肠道肌层兴奋性降低,肌层收缩减弱,引起糖尿病胃肠病变的一个重要机制.展开更多
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
文摘目的:了解糖尿病大鼠胃肠动力障碍时,回肠肌间神经丛有无形态学异常,以及第Ⅰ组代谢型谷氨酸受体mGluR1、mGluR5的表达变化,探讨谷氨酸能神经在糖尿病胃肠病变发生中的作用.方法:40只大鼠随机分为糖尿病组和对照组,给与高脂饮食结合腹腔注射STZ 30 mg/kg造糖尿病模型.运用肌间神经丛铺片观察谷氨酸能神经的分布及形态特征,并对其神经节和神经元进行定量研究,以及运用免疫荧光染色和RT-PCR方法观察大鼠回肠肠神经系统肌间神经丛的代谢型谷氨酸受体mGluR1、mGluR5的表达变化.结果:糖尿病大鼠肠神经系统肌间神经丛的谷氨酸能神经节和神经元的数目较对照组明显减少(mGluR1:4.5±3.1 vs 7.3±2.4;142.25±28.24vs 175.34±34.83,均P<0.05;mGluR5:4.3±2.1 vs 7.9±2.8,133.37±35.73 vs 168.34±32.66,均P<0.05),荧光强度较对照组减弱(mGluR1:145.23±28.78 vs 167.72±30.56,均P<0.05;mGluR5:141.54±18.46 vs 172.53±29.74,均P<0.05),mGluR1、mGluR5受体mRNA表达减少(1.05±0.27 vs 1.43±0.47,0.95±0.30vs 1.60±0.39,均P<0.01).结论:糖尿病大鼠回肠肠壁的肌间神经丛的神经节和神经元数目减少,以及兴奋性递质受体mGluR1、mGluR5的表达减少是导致胃肠道肌层兴奋性降低,肌层收缩减弱,引起糖尿病胃肠病变的一个重要机制.
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.
