茶多酚对胰岛素分泌和胰岛内钙离子浓度的影响

Effect of tea polyphenols on insulin secretion and Ca^(2+) concentration in rat islet

目的研究茶多酚对胰岛素分泌和胰岛内Ca^(2+)浓度的影响。方法在显微镜下挑选单个胰岛,收集5个胰岛为1组,放置在含有不同浓度(0～150μg/mL)茶多酚的葡萄糖溶液中孵化,检测上清液中胰岛素的含量;收集100个胰岛个体,用Fluo-3/AM染色,放置于含不同浓度茶多酚的葡萄糖溶液中孵化,用激光扫描共聚焦显微镜检测胰岛个体内Ca^(2+)荧光信号强度。结果与对照组(不含茶多酚的葡萄糖孵化溶液)相比,不同茶多酚浓度孵化液中胰岛素的浓度提高2～11倍(P<0.01);胰岛内Ca^(2+)荧光信号强度提高3～30倍(P<0.01)。结论茶多酚能够提高胰岛内Ca^(2+)浓度,并在胰岛水平上促进胰岛素分泌。

Objective To study the effect of tea polyphenols（TP） on insulin secretion and Ca^（2＋） concentration in rat islet.Methods Islets were obtained from the healthy rats,with the collection of five islets for each group.They were incubated in the solution containing different concentrations of glucose and TP.The released insulin from islets was measured.A hundred of islets were collected and dyed with Fluo-3/AM,and then incubated in the same conditions as above.The Ca^（2＋） fluorescence signal intensities of the islets,which were related with the Ca^（2＋） concentration in islet,were detected with laser scanning con-focal microscopy.Results Compare with the control groups（only glucose solutions with absenting TP）,insulin release with TP increased 2-11 times（P0.01）.The Ca^（2＋） fluorescence signal intensities of the islets increased from at least 3 times to up to 30 times（P0.01）.Conclusion TP can improve the Ca^（2＋） concentration and insulin secretion in islet.