5-Hydroxytryptamine hyperpolarizes CA3 hippocampal pyramidal cells through an increase in potassium conductance.
5-Hydroxytryptamine hyperpolarizes CA3 hippocampal pyramidal cells through an increase in potassium conductance.
复制标题
5-Hydroxytryptamine 通过增加钾电导使 CA3 海马锥体细胞超极化。
DOI：
10.1016/0304-3940(91)90065-2
复制
发表时间：
1991
影响因子：
2.5
通讯作者：
Choi,KC
中科院分区：
文献类型：
--
作者：
Beck,SG;Choi,KC
从CA 3子区记录的海马锥体细胞的放电率被5-羟色胺（5-HT，5-羟色胺）或来自中缝的上行多巴胺能纤维的电刺激抑制。5-HT产生的这种抑制作用的作用机制尚未确定。应用细胞内记录技术，观察了5-HT灌流对海马CA 3区锥体细胞膜特性的影响。在16个测试的细胞中，有15个，5-HT引起了明显的超极化伴随着膜电阻的降低。超极化没有改变与氯化钾或钾甲基硫酸盐电极;超极化由5-HT不存在时，电极充满氯化铯。使用单电极电压钳技术，在3 mM KCl缓冲液中确定5-HT介导的反应的逆转电位为− 105.5 mV。基于这些结果，我们得出结论，5-HT抑制CA 3海马锥体细胞兴奋性的作用机制是由于钾电导的增加。
The firing rate of hippocampal pyramidal cells recorded from the CA3 subfield is inhibited by 5-hydroxytryptamine (5-HT, serotonin) or by electrical stimulation of the ascending serotonergic fibers from the raphe. The mechanism of action of this inhibitory effect produced by 5-HT has not been determined. Intracellular recording techniques in the hippocampal slice preparation were used to measure the effect of 5-HT perfusion on membrane properties of CA3 pyramidal cells. In 15 out of 16 cells tested, 5-HT elicited a pronounced hyperpolarization concomitant with a decrease in membrane resistance. The hyperpolarization was not altered with either potassium chloride or potassium methylsulphate electrodes; the hyperpolarization by 5-HT was not present when electrodes were filled with cesium chloride. The reversal potential of the 5-HT mediated response was determined to be − 105.5 mV in 3 mM KCl buffer using single electrode voltage clamp techniques. Based on these results we conclude that the mechanism of action of the 5-HT inhibition of CA3 hippocampal pyramidal cell excitability is due to an increase in potassium conductance.