谷氨酸从人大脑皮层的钙依赖性释放。

Calcium-dependent release of glutamate from human cerebral cortex.

作者信息

Hegstad E, Haugstad T S, Hauglie-Hanssen E, Langmoen I A

机构信息

Institute for Surgical Research, Rikshospitalet, National Hospital, University of Oslo, Norway.

出版信息

Brain Res. 1992 Jul 10;585(1-2):340-2. doi: 10.1016/0006-8993(92)91233-5.

DOI:10.1016/0006-8993(92)91233-5

PMID:1355003

Abstract

The release of the excitatory amino acids glutamate and aspartate from human neocortex was investigated in vitro by utilizing brain tissue removed during anterior temporal lobectomies for tumor or epilepsy. Depolarization (50 mM K+) increased the glutamate release to 291% of control (809 pmol/mg/min) during blocked synaptic transmission and to 669% (1859 pmol/mg/min) when synaptic transmission was not blocked. Aspartate release increased to 141% (326 pmol/mg/min) and 178% (412 pmol/mg/min) respectively. The difference between release with and without blocked synaptic transmission was statistically significant only for glutamate (P less than 0.01). These data provides evidence for a Ca(2+)-dependent release of glutamate, supporting a possible role of this amino acid as a neurotransmitter in human neocortex.

摘要

利用因肿瘤或癫痫而接受前颞叶切除术时切除的脑组织，在体外研究了人新皮质中兴奋性氨基酸谷氨酸和天冬氨酸的释放。去极化（50 mM K +）在突触传递受阻时使谷氨酸释放增加至对照值的291%（809 pmol/mg/min），而在突触传递未受阻时增加至669%（1859 pmol/mg/min）。天冬氨酸释放分别增加至141%（326 pmol/mg/min）和178%（412 pmol/mg/min）。仅谷氨酸在突触传递受阻和未受阻时的释放差异具有统计学意义（P小于0.01）。这些数据为谷氨酸的Ca(2+)依赖性释放提供了证据，支持了这种氨基酸在人新皮质中作为神经递质的可能作用。