大鼠脑突触体在酸性氨基酸递质电生性摄取过程中对Na+/K+泵活性的刺激作用。

Stimulation of the Na+/K+ pump activity during electrogenic uptake of acidic amino acid transmitters by rat brain synaptosomes.

作者信息

Erecińska M

机构信息

Department of Pharmacology, University of Pennsylvania, School of Medicine, Philadelphia 19104-6084.

出版信息

J Neurochem. 1989 Jan;52(1):135-9. doi: 10.1111/j.1471-4159.1989.tb10907.x.

DOI:10.1111/j.1471-4159.1989.tb10907.x

PMID:2562804

Abstract

Addition of D-aspartate, a substrate for the high-affinity transport of acidic amino acid transmitters, to suspensions of rat brain synaptosomes increased the rate of O2 consumption, uptake of 86Rb, and transport of 2-[3H]deoxyglucose. Stimulation of all three processes was abolished in the presence of ouabain. D-Aspartate had no effect on respiration in the medium in which NaCl was replaced by choline chloride. The ratio of the ouabain-sensitive increase in 86Rb uptake to that in O2 consumption was 12 to 1, which gives a calculated 86Rb(K+)/ATP of 2. It is concluded that electrogenic, high-affinity transport of sodium-D-aspartate into synaptosomes stimulates the activity of the Na+/K+ pump through an increase in [Na+]i.

摘要

向大鼠脑突触体悬浮液中添加 D-天冬氨酸（一种酸性氨基酸递质高亲和力转运的底物），可提高耗氧率、86Rb 的摄取率以及 2-[3H]脱氧葡萄糖的转运率。在哇巴因存在的情况下，这三个过程的刺激作用均被消除。D-天冬氨酸对用氯化胆碱替代氯化钠的培养基中的呼吸作用没有影响。哇巴因敏感的 86Rb 摄取增加与耗氧增加的比率为 12 比 1，由此计算出的 86Rb(K+)/ATP 为 2。得出的结论是，钠-D-天冬氨酸向突触体的电生性高亲和力转运通过增加[Na+]i 来刺激 Na+/K+泵的活性。