胰淀素对高糖刺激下大鼠胰岛细胞瘤细胞系Ins-1ATP敏感性钾通道的影响  

Effects of islet amyloid polypeptide on electrophysiological characteristics of KATe channel in rat islet cell tumor cell line Ins-1

作　　者：肖金凤[1] 李晓通[1] 赵新[1] 贺秉军[2] 商学良 韩丽鑫[2] 吴广彦 丁雪梅[1] 朱铁虹[1] 

机构地区：[1]天津医科大学总医院内分泌科,300052 [2]南开大学生命科学院

出　　处：《中华糖尿病杂志》2015年第11期694-697,共4页CHINESE JOURNAL OF DIABETES MELLITUS

摘　　要：目的观察胰淀素短时间作用对高糖刺激的大鼠胰岛细胞瘤细胞系Ins-1的ATP敏感性钾通道fK。通道）的影响。方法以Ins-1细胞为研究对象，随机分为16．7mmol／L葡萄糖处理组及0．1、1、10μmol／L胰淀素预处理组，采用全细胞膜片钳技术分析不同浓度胰淀素短时间作用对高糖刺激下Ins-1细胞KKIP通道电生理学特性的影响，同时收集细胞培养上清液应用酶联免疫吸附法（ELISA）测定孵育液中的胰岛素含量。组间数据比较采用t检验。结果与16．7mmol／L葡萄糖组相比，0．1μmol／L胰淀素预处理组胰岛索释放量及KNTP通道半数激活电压（V0.5，）差异均无统计学意义[分别为（5．57±0．93）比（4．95±0．49）μg／L和（9．4±1．4）比（13．0±2．4）mV，t=1．022、-2．244，均P〉0、05]；而1μmol／L及10μmol／L胰淀素预处理组胰岛素释放量分别显著下降为（3．44＋0．32）和（2．23±0．55）gg／L（t=3．751、5．354，均P〈0．05），而V。则分别显著提高到（28．2±2．7）和（33．3±2．1）mV（t=-5．053、-10．707，均P〈0．05）。结论高浓度咦淀素短时间作用可通过抑制高糖对K。，通道的关闭作用进而抑制Ins．1细胞胰岛素分泌。Objective To observe the effects of islet amyloid polypeptide （IAPP） on KATP channel in rat islet cell tumor cell line Ins-1 stimulated by high concentration of glucose. Methods Ins-1 cells, as the research object, were randomly divided into 16.7 mmol/L glucose control group and 0.1, 1, 10 μmol/L amylin pretreatment group. Whole cell patch clamp technique was employed to study the influences of short exposure to IAPP on electrophysiological characteristics of K channel upon glucose stimulation. Meanwhile, insulin secretion was measured by enzyme-linked immunoassay. Group data were compared by using t test with the P value set at 0.05. Results The insulin secretion and half-maximal activation voltage （V05} of KA,rp in cells incubated with 16.7 mmol/L glucose were （5.57 ± 0.93） μg/L and （9.4 ± 1.4） mV, respectively; and those were （4.95±0.49）μg/L and （13.0±2.4） mV in ceils pretreated with 0.1 μmol/L amylin; and there was no significant differences between the two groups（t=l.022,-2.244, both P〉0.05）. While the insulin secretion in cells pretreated with 1 μmol/L and 10 μmol/L amylin significantly decreased （（3.44± 0.32）μg/L and （2.23±0.55） μg/L, respectively） and the V0.5 increased significantly（（28.2±2.7） mV and （33,3± 2.1） mV, respectively） when compared with those in cells treated with 16.7 mmol/L glucose （t=3.751, 5.354,-5.053,- 10.707, all P〈0.05）. Conclusions Short-term exposure to high concentration of amylin inhibites the closure of ATP-sensitive potassium channels upon glucose stimulation, thus may ultimately lead to the reduction of insulin secretion in Ins-1 cells.

关 键 词：胰淀素 大鼠胰岛细胞瘤细胞系Ins-1 ATP敏感性钾通道 

分 类 号：R587.1[医药卫生—内分泌]