Zeise M L, Batsche K, Wang R Y
Department of Psychiatry and Behavioral Sciences, State University of New York at Stony Brook 11794-8790.
Brain Res. 1994 Jul 18;651(1-2):337-41. doi: 10.1016/0006-8993(94)90715-3.
The effects of the serotonin (5-HT)3 receptor agonist, 2-methyl-5-hydroxytryptamine (2-methyl-5-HT), were studied in CA1 pyramidal cells of the rat hippocampus in vitro using the whole cell gigaseal technique. 2-Methyl-5-HT (10 and 50 microM) did not change significantly the electrophysiologic properties of the cells but reversibly reduced excitatory and inhibitory postsynaptic potentials evoked by stimulation of the Schaffer collaterals. The onset and termination of this effect was in the order of minutes and no desensitization was observed. The selective 5-HT3 receptor antagonist, granisetron, when applied as a pretreatment completely prevented but did not reverse this action when given after administration of 2-methyl-5-HT while the non-specific 5-HT1,2 receptor antagonist, metergoline, was ineffective. These results suggest that the activation of 5-HT3 receptors reduces the efficacy of glutamatergic synaptic transmission in this area.
采用全细胞膜片钳技术，在体外研究了5-羟色胺（5-HT）3受体激动剂2-甲基-5-羟色胺（2-甲基-5-HT）对大鼠海马CA1锥体细胞的作用。2-甲基-5-HT（10和50微摩尔）对细胞的电生理特性无显著影响，但可可逆性降低刺激Schaffer侧支所诱发的兴奋性和抑制性突触后电位。这种效应的起始和终止时间以分钟计，未观察到脱敏现象。选择性5-HT3受体拮抗剂格拉司琼预处理时可完全阻断此作用，但在2-甲基-5-HT给药后给予则不能逆转该作用，而非特异性5-HT1、2受体拮抗剂麦角林则无效。这些结果提示，5-HT3受体的激活降低了该区域谷氨酸能突触传递的效能。
