CALCIUM-DEPENDENT TRANSMITTER SECRETION FROM FIBROBLASTS - MODULATION BY SYNAPTOTAGMIN-I

被引：69

作者：

MORIMOTO, T ^{[1
]}

POPOV, S ^{[1
]}

BUCKLEY, KM ^{[1
]}

POO, MM ^{[1
]}

机构：

[1] HARVARD UNIV,SCH MED,DEPT NEUROBIOL,BOSTON,MA 02115

来源：

NEURON | 1995年 / 15卷 / 03期

关键词：

D O I：

10.1016/0896-6273(95)90156-6

中图分类号：

Q189 [神经科学];

学科分类号：

071006 ;

摘要：

Following endocytic uptake of acetylcholine (ACh), CHO fibroblasts exhibit Ca2+-dependent spontaneous quantal ACh release and depolarization-evoked ACh release, as detected by a whole-cell voltage-clamped myocyte in contact with the fibroblast. CHO fibroblasts transfected with synaptotagmin I, an integral membrane protein of synaptic vesicles, showed a reduced spontaneous quantal ACh release and an enhanced Ca2+-evoked ACh release, as compared with control cells. Biochemical and ultrastructural studies of endocytic activity using horseradish peroxidase as a marker further confirmed the inhibitory action of synaptotagmin I on spontaneous vesicular exocytosis and on elevated exocytosis induced by Ca2+. Through inhibition of exocytosis at the resting intracellular concentration of Ca2+ and removal of the inhibition upon depolarization-induced Ca2+ entry, synaptotagmin I could enhance the efficiency of excitation-secretion coupling.

引用

页码：689 / 696

页数：8

共 33 条

[1] EXOCYTOSIS OF PINOCYTIC CONTENTS BY CHINESE-HAMSTER OVARY CELLS [J].