Yakel J L, Jackson M B
Department of Biology, University of California, Los Angeles 90024.
Neuron. 1988 Sep;1(7):615-21. doi: 10.1016/0896-6273(88)90111-0.
Serotonin (5-HT) induces a large inward current accompanied by a conductance increase when applied focally to either neurons of mouse hippocampal cultures or cells of the NG108-15 clonal cell line. In both systems, the response is blocked by ICS 205-930, curare, and metoclopramide, while 2-methyl-5-HT is an agonist. The actions of ICS 205-930 and 2-methyl-5-HT indicate that the response is mediated by the 5-HT3 receptor. In NG108-15 cells the response activated in as little as 35 ms. The rapidity of the response suggests a direct coupling between the 5-HT3 receptor and a channel, which are probably both part of a single membrane protein. In both cell types, prolonged application of 5-HT resulted in desensitization; the rates of desensitization were accelerated by the adenylate cyclase activator forskolin. The 5-HT3 receptor has much in common with the nicotinic receptor and is probably involved in rapid synaptic transmission in the mammalian brain. Since this response is modulated by manipulations that elevate intracellular cAMP levels, the central synapses in which this receptor operates may exhibit plasticity.
当向小鼠海马神经元培养物中的神经元或NG108 - 15克隆细胞系的细胞局部施加5 - 羟色胺（5 - HT）时，它会诱导出一个大的内向电流，同时伴随着电导增加。在这两种系统中，该反应被ICS 205 - 930、箭毒和胃复安阻断，而2 - 甲基 - 5 - HT是一种激动剂。ICS 205 - 930和2 - 甲基 - 5 - HT的作用表明该反应是由5 - HT3受体介导的。在NG108 - 15细胞中，该反应在短短35毫秒内就被激活。反应的快速性表明5 - HT3受体与通道之间存在直接偶联，它们可能都是单一膜蛋白的一部分。在这两种细胞类型中，长时间应用5 - HT会导致脱敏；腺苷酸环化酶激活剂福斯可林加速了脱敏速率。5 - HT3受体与烟碱样受体有许多共同之处，可能参与哺乳动物大脑中的快速突触传递。由于这种反应受到提高细胞内cAMP水平的操作的调节，该受体起作用的中枢突触可能表现出可塑性。
