慢性乙醇在体外抑制大鼠海马5-羟色胺的“刺激-分泌”偶联机制。

Chronic ethanol inhibits rat hippocampal "stimulus-secretion" coupling mechanism for 5-hydroxytryptamine in vitro.

作者信息

Wu P H, Naranjo C A, Fan T

出版信息

Neurochem Res. 1986 Jun;11(6):801-12. doi: 10.1007/BF00965205.

Abstract

Effects of ethanol on serotonergic neurotransmission were investigated in crude mitochondrial fraction (P2 fraction) from rat brain hippocampus and hypothalamus. The [14C]5-HT preloaded P2 fraction was exposed to 45 mM KCl to induce 5-hydroxytryptamine release in vitro. Ethanol in vitro did not produce any significant inhibition of [14C]5-HT release until its concentration was greater than 100 mM. The K+-evoked 45Ca uptake of hippocampal P2 fraction was unaffected by 100 mM. However, 200 mM ethanol inhibited approximately 63% of K+-evoked 45Ca uptake. Chronic ethanol (10 g/kg/day) for 6 days inhibited [14C]5-HT release from hippocampus whereas it did not affect [14C]5-HT release from hypothalamus. Results indicate that chronic ethanol treatment may decrease serotonergic neurotransmission in selective brain regions. The reduction in 5-hydroxytryptamine release was the result of inhibition in "stimulus-secretion" coupling mechanism.

摘要

研究了乙醇对大鼠脑海马体和下丘脑粗线粒体组分（P2组分）中血清素能神经传递的影响。将预先加载了[14C]5-羟色胺的P2组分暴露于45 mM氯化钾中，以在体外诱导5-羟色胺释放。体外乙醇在其浓度大于100 mM之前不会对[14C]5-羟色胺释放产生任何显著抑制作用。100 mM乙醇对海马体P2组分中钾离子诱发的45钙摄取没有影响。然而，200 mM乙醇抑制了约63%的钾离子诱发的45钙摄取。连续6天给予慢性乙醇（10 g/kg/天）可抑制海马体中[14C]5-羟色胺的释放，但不影响下丘脑[14C]5-羟色胺的释放。结果表明，慢性乙醇处理可能会降低选择性脑区的血清素能神经传递。5-羟色胺释放的减少是“刺激-分泌”偶联机制受到抑制的结果。