大鼠胰腺β细胞钙离子平衡的多钙库机制

Intracellular calcium store and its function in insulin secretion was studied at single beta cell using patch clamp technique and microfluorescent measurement of intracellular calcium. It shows that there are three calcium stores in beta cells: L-arginine sensitive mitochondria store as well as IP3 calcium store and Ryrodine store. IP3 calcium store release three times as fast as Ryrodine store and spend more time to deplenish. IP3 and Ryrodine calcium stores play important role in modulating the release of insulin, which evidently affect the second phase of insulin secretion. Moreover, a sodium channel readily inactivated at rest status was found in beta cells and their significance is to be studied.

在单个大鼠胰腺β细胞上，采用膜片钳和胞内钙显微荧光测量方法，研究细胞内钙离子库对β细胞内钙平衡的作用。我们最近的工作已证明大鼠β细胞上同时存在三种独立的钙库。本申请将进一步研究这三种钙库对钙平衡的相对贡献及与外钙内流的相对地位。在此基础上，研究钙库对胰岛素分泌的调控作用，从而探讨钙平衡失调与糖尿病的关系。