Effect of calcium antagonist verapamil on tolbutamide-induced insulin release from islet?-cells of rats / 中华内分泌代谢杂志

ABSTRACT

Objective To investigate the effect of calcium antagonist verapamil on the function of rat?- cells and tolbutamide (D860)-induced insulin release.Methods Insulin released from isolated islets were measured in control,verapamil,D860,and verapamil+D860 groups.Furthermore,intravenous glucose tolerance test (IVGTT) was conducted in acute experiments treated with verapamil and D860 respectively to assess?-cell function in rats with the same allocation as in vitro.Another IVGTT was performed in the end of 4 weeks' treatment.The insulin contents in pancreas were assayed and pancreas islets morphology were observed with immunohistochemistry.Results Verapamil could inhibit insulin release from isolated islets.Verapamil group was [(1.244?0.082)ng?ml~(-1)?islet~(-1)]and control group (2.623?0.226) ng?ml~(-1)?islet~(-1)(P0.05).Also,similar results were obtained in normal rats during acute experiments and verapamil reduce the hypoglycemic effect promoted by D860. However,above results were not observed in the end of 4 weeks experiments,and no difference for insulin content and morphological change in islets was found among four groups.Conclusion Treatment of verapamil chronically does not impair islet function and interfere with the hypoglycemic effect of D860 in rats .