胰淀素对大鼠胰岛β细胞电压门控L-型钙通道的影响  

The effects of amylin on the islet It-cells voltage-gated L-calcium channels in rats

作　　者：朱铁虹[1] 王银霞[2] 贺秉军[3] 臧晶晶[3] 刘东波[3] 丁雪梅[4] 

机构地区：[1]天津医科大学总医院内分泌科,300052 [2]内蒙古医学院附属医院神经内科 [3]南开大学生命科学院 [4]天津市武清区人民医院

出　　处：《中华内科杂志》2009年第6期488-491,共4页Chinese Journal of Internal Medicine

基　　金：天津市科委自然科学基金（05YFMJC04000）

摘　　要：目的观察胰淀素对大鼠胰岛β细胞电压门控L-型钙通道的影响。方法用全细胞膜片钳技术观察胰淀素作用前后胰岛βB细胞电压门控L-型钙通道门控特性、电流变化。结果在葡萄糖5．5mmol／L条件下，大鼠胰岛β细胞L-型钙通道电流约在-40mV激活，＋20mV左右达高峰，峰值约为-120pA，胰岛素分泌量为（0．76±0．12）μg／L；16．7mmol／L葡萄糖刺激下峰电流电压左移、峰电流达-140pA左右，胰岛素分泌量为（1．78±0．13）μg／L。用0．5、1．0．5．0、10．0μmo]／L浓度胰淀素分别孵育胰岛B细胞，在5．5、16．7mmoL／L葡萄糖条件下，0．5、1．0μmol／L胰淀素浓度的峰电位激活电压、电流、胰岛素分泌量与对照组相比，差异均无统计学意义，在5．5mmol／L葡萄糖条件下，5．0、10．0μmol／L胰淀素浓度的激活电压增加为一30mV，峰电流分别减小至-80pA、-60pA左右，胰岛素分泌量分别降低至（0．49±0．11）、（0．36±0．12）μg／L；在16．7mmol／L葡萄糖条件下，激活电压由-40mV增加到-30mV，峰电流分别减小至-80pA、-40pA，胰岛素分泌量分别降低至（1．20±0．13）、（0．89±0．14）μg/L，与对照组相比差异具有统计学意义。结论葡萄糖刺激胰岛β细胞电压门控L-型钙通道开放与胰岛素分泌同步，胰淀素抑制胰岛β细胞电压门控L-型钙通道开放和抑制胰岛素分泌作用同步并与其作用浓度正相关。Objective To observe the effect of amylin on the islet β-cells vohage-gated L-calcium channels in rats. Method Patch clamp technique was employed in the observation of the features and changes of electric current of islet β-cells vohage-gated L-calcium channels before and after using amylin. Results In the glucose environment of 5.5 mmol/L, the electric current of rat islet β-cells voltage-gated L-calcium channels was activated at -40 mV and reached the peak at about ＋ 20 mV, with a peak value of about - 120 pA and the insulin secretion level was（0. 76 ±0. 12） p.g/L Under the stimulation of glucose of 16.7 mmol/L, the peak current voltage moved to the left and increased up to - 140 pA and the level of insulin secretion measured （ 1.78 ± 0. 13 ）μg/L. Hatch islet β-cells in amylin at the concentrations of 0. 5, 1.0, 5.0 and 10. 0 μmol/L, respectively. It was observed that in the 0. 5μ mol/L and 1.0 μmol/L groups, there was no remarkable change in the peak potential activation voltage, current, and insulin secretion volume in comparison with the control group. However, in the environment of 5.5 mmol/L glucose, the increase of activation voltage of the 5.0 and 10. 0 μmoL/L groups was - 30 mV, with the peak current reduced to approximately -80 pA and -60 pA and the insulin secretion decreased to （0.49 ±0. 11 ） μg/L and （0. 36 ±0. 12） μg/L respectively. Under the concentration of 16.7 mmol/L glucose, the activation voltage increased from -40 mV up to -30 mV and the peak current reduced to -80 pA and -40 pA. In the meantime, the insulin secretion decreased respectively to （ 1.20 ±0. 13 ） μg/L and （ 0. 89 ±0. 14 ） μg/L, which is of significance. Conclusion The secretion of insulin is synchronized with the opening of the islet β-cells voltage-gated L-calcium channels at the stimulation of glucose. The amylin inhibition of the insulin secretion is also synchronized with the opening of islet β-cells vohage-gated L-calcium channels and it＇s in a positive concentration-dependen

关 键 词：钙通道 L型 胰岛素分泌细胞 胰淀素 

分 类 号：R686[医药卫生—骨科学]