TITYUSTOXIN-MEDIATED NA+ INFLUX IS MORE EFFICIENT THAN KCL DEPOLARIZATION IN PROMOTING CA2+-DEPENDENT GLUTAMATE RELEASE FROM SYNAPTOSOMES

被引：21

作者：

ROMANOSILVA, MA

RIBEIROSANTOS, R

GOMEZ, MV

MORAESSANTOS, T

BRAMMER, MJ

机构：

[1] INST PSYCHIAT, DECRESPIGNY PK, LONDON SE5 8AF, ENGLAND

[2] UNIV FED MINAS GERAIS, DEPT BIOCHEM & IMMUNOL, BR-30000 BELO HORIZONTE, MG, BRAZIL

[3] UNIV FED MINAS GERAIS, DEPT PHARMACOL, BR-30000 BELO HORIZONTE, MG, BRAZIL

[4] UNIV FED MINAS GERAIS, FAC PHARM, BR-30000 BELO HORIZONTE, MG, BRAZIL

来源：

NEUROSCIENCE LETTERS | 1994年 / 169卷 / 1-2期

关键词：

TITYUSTOXIN; SYNAPTOSOME; CALCIUM; GLUTAMATE; NEUROTRANSMITTER RELEASE;

D O I：

10.1016/0304-3940(94)90363-8

中图分类号：

Q189 [神经科学];

学科分类号：

071006 ;

摘要：

The scorpion venom toxin, tityustoxin (TsTX), causes rapid, dose-dependent increases in intracellular free Ca2+ ([Ca2+]i) and glutamate release in rat cerebrocortical synaptosomes. These effects are completely abolished by the Na+ channel blocker tetrodotoxin (TTX). The increase in [Ca2+]i is completely dependent on extracellular Ca2+ but the increased glutamate release has both Ca2+-dependent and -independent components. Comparison of the effects of TsTX with those of depolarising concentrations of KCl reveals that TsTX is more effective, both in raising [Ca2+]i and promoting Ca2+-dependent and -independent glutamate release. These data suggest that the Ca2+-dependent glutamate release caused by TsTX is only partly due to Ca2+ entry through voltage-sensitive Ca2+ channels.

引用

页码：90 / 92

页数：3

共 13 条

[1] THE CALCIUM SIGNAL FOR TRANSMITTER SECRETION FROM PRESYNAPTIC NERVE-TERMINALS [J].