氨对分离的星形胶质细胞中谷氨酸代谢酶的急性代谢影响。

Acute metabolic effects of ammonia on the enzymes of glutamate metabolism in isolated astroglial cells.

作者信息

Subbalakshmi G Y, Murthy C R

机构信息

School of Life Sciences, University of Hyderabad, Hyderabad 500134 AP, India.

出版信息

Neurochem Int. 1983;5(5):593-7. doi: 10.1016/0197-0186(83)90051-7.

DOI:10.1016/0197-0186(83)90051-7

PMID:20487986

Abstract

Enzymes of glutamate metabolism were studied in the astrocytes isolated from rats injected with a large dose of ammonium acetate and compared with those isolated from controls. The activities of glutamate dehydrogenase (GDH) and glutaminase decreased while those of glutamine synthetase (GS) and aspartate aminotransferase (AAT) increased both in convulsive and comatose states. The activity of alanine aminotransferase (A1AT) increased only in convulsive state. The results suggested that glutamate required for the formation of glutamine in astrocytes might have its origin in nerve endings and the depletion of citric acid cycle intermediates might occur in nerve endings at least in acute ammonia toxicity.

摘要

对注射大剂量醋酸铵的大鼠分离出的星形胶质细胞中的谷氨酸代谢酶进行了研究，并与从对照组分离出的细胞进行了比较。在惊厥和昏迷状态下，谷氨酸脱氢酶（GDH）和谷氨酰胺酶的活性降低，而谷氨酰胺合成酶（GS）和天冬氨酸转氨酶（AAT）的活性增加。丙氨酸转氨酶（A1AT）的活性仅在惊厥状态下增加。结果表明，星形胶质细胞中谷氨酰胺形成所需的谷氨酸可能起源于神经末梢，至少在急性氨中毒时，神经末梢可能会出现柠檬酸循环中间产物的耗竭。