Actions of 5-hydroxytryptamine on myenteric neurons in guinea pig gastric antrum.
Actions of 5-hydroxytryptamine on myenteric neurons in guinea pig gastric antrum.
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5-羟色胺对豚鼠胃窦肌间神经元的作用。
DOI：
10.1152/ajpgi.1992.263.6.g838
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发表时间：
1992
期刊：
影响因子：
--
通讯作者：
Wood,JD
中科院分区：
文献类型：
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作者：
Tack,JF;Janssens,J;Vantrappen,G;Wood,JD
应用细胞内记录方法研究了5-羟色胺（5-HT）对257个豚鼠胃窦肌间神经元的作用。应用5-HT引起三种类型的突触后反应。一个快速激活去极化反应伴随着输入电阻下降，并迅速脱敏重复应用。它由5-HT 3受体介导。慢激活性去极化，伴随着输入电阻的增加和兴奋性的增强，主要观察到后超极化/2型神经元。它被抑制的促动力苯甲酰胺化合物伦扎必利，而经典的5-HT 1 -4受体拮抗剂没有影响，表明参与5-HT 1 p受体所描述的小肠神经元。一个持久的超极化反应，伴随着降低输入电阻，观察到在一个小的神经元子集。这种反应似乎是由5-HT 1a受体介导的。灌流5-HT可剂量依赖性地抑制突触前5-HT 1a受体介导的烟碱胆碱能快兴奋性突触后电位（EPSP）。5-HT对慢EPSP也有突触前抑制作用。
Intracellular recording methods were used to study the actions of 5-hydroxytryptamine (5-HT) on 257 myenteric neurons in the guinea pig gastric antrum. Application of 5-HT caused three types of postsynaptic responses. A fast-activating depolarizing response was accompanied by a decreased input resistance and desensitized quickly to repeated applications. It was mediated by a 5-HT3 receptor. A slowly activating depolarization, accompanied by an increase in the input resistance and enhancement of the excitability, was mainly observed in after hyperpolarizing/type 2 neurons. It was suppressed by the prokinetic benzamide compound renzapride, while classical 5-HT1-4 receptor antagonists had no effect, suggesting the involvement of a 5-HT1p receptor as described in small intestinal neurons. A long-lasting hyperpolarizing response, accompanied by a decreased input resistance, was observed in a small subset of neurons. This response seemed to be mediated by a 5-HT1a receptor. Superfusion of 5-HT caused a dose-dependent inhibition of the stimulus-evoked nicotinic cholinergic fast excitatory postsynaptic potential (EPSP), which was mediated by a presynaptic 5-HT1a receptor. 5-HT also presynaptically inhibited the slow EPSP.