电压依赖性钾通道在京尼平苷调控大鼠胰岛素分泌中的作用  

The Role of Voltage-dependent Potassium Channel in Geniposide-induced Insulin Secretion in Rats

作　　者：刘云峰[1] 丁亚琴[2] 钟向琴 任乐乐[2] 白涛[1,2] 刘萌萌[2] 章毅[2] 

机构地区：[1]山西医科大学第一医院,太原030001 [2]山西医科大学

出　　处：《中西医结合心脑血管病杂志》2016年第22期2626-2628,共3页Chinese Journal of Integrative Medicine on Cardio-Cerebrovascular Disease

基　　金：国家自然科学基金(No.81273564;81373464;81670710);山西省留学回国人员科技活动项目择优资助(No.2016-97)

摘　　要：目的研究电压依赖性钾（Kv）通道在京尼平苷调控大鼠胰岛素分泌机制中的作用。方法采用放免法检测大鼠胰岛组织的胰岛素分泌情况,膜片钳技术记录胰岛β细胞Kv电流和动作电位时程（APD）。结果在8.3 mmol/L葡萄糖条件下,京尼平苷（0-100μmol/L）可剂量依赖性地增加胰岛素分泌含量,在10μmol/L时基本达最大促分泌效应,低糖（2.8 mmol/L）情况下则没有作用。膜片钳实验数据表明,京尼平苷剂量依赖性地（0-100μmol/L）降低Kv通道电流密度,并在10μmol/L的浓度下发挥最大抑制作用,并明显延长了动作电位时程。结论京尼平苷在胰岛β细胞中通过抑制Kv、延长APD发挥促胰岛素分泌作用。Objective To explore the role of voltage-dependent potassium（ Kv） channel in the mechanism of geniposide-induced insulin secretion in rats. Methods We evaluated the direct effects of geniposide on β-cell function using rat pancreatic islets and dispersed single cells.Patch β-clamp recordings were applied to measure Kv channels,action potential duration（ APD）. The level of insulin secretion and the content of cyclic AMP in the culture medium were measured with radioimmunoassay. Results Geniposide（0 to 100 μmol / L） potentiated insulin secretion from pancreatic islets in a dose-dependent manner under 8. 3 mmol / L glucose conditions but not 2. 8 mmol / L,and a maximal increase was observed when islets were exposed to geniposide at a concentration of 10 μmol / L. The current-voltage relationship curve obtained in patch-clamp experiments demonstrated that geniposide（0 to 100 μmol / L） dose-dependently decreased the current densities through Kv channels and exerted a maximal inhibitory effect at the concentration of 10 μmol / L. What＇s more,we detected that geniposide significantly prolonged APD. Conclusion Geniposide can promote insulin secretion by inhibiting Kv and prolonging APD in islet β cells.

关 键 词：京尼平苷 胰岛素分泌 电压依赖性钾通道 动作电位 

分 类 号：R587.1[医药卫生—内分泌]