Brownfield M S, Greathouse J, Lorens S A, Armstrong J, Urban J H, Van de Kar L D
Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison.
Neuroendocrinology. 1988 Apr;47(4):277-83. doi: 10.1159/000124925.
In this study we have evaluated a possible role for brain serotoninergic neurons in the regulation of vasopressin secretion using pharmacological methods. In order to accomplish this, we have developed a specific and sensitive vasopressin radioimmunoassay along with a highly reproducible plasma extraction protocol. These tools were used to evaluate the plasma vasopressin response to several pharmacological challenges in conscious rats. Treatment with the serotonin (5-HT) releaser p-chloroamphetamine caused a significant increase in plasma vasopressin concentration. This effect was blocked by posterior hypothalamic deafferentation which separates serotonin cell bodies in the midbrain from their nerve terminals in the hypothalamus. Administration of graded doses of several 5-HT agonists had no effect. However, treatment with MK212, a serotonin agonist with 5-HT1 + 5-HT2 activity, induced a significant increase in plasma vasopressin concentration. The effect of MK212 on plasma vasopressin was completely abolished by the selective 5-HT2 receptor blocker LY53857. These studies confirm and extend studies by others that provide pharmacological evidence for serotoninergic regulation of vasopressin secretion via a selective 5-HT2 receptor mechanism. The specific neuroanatomical site(s) where serotonin exerts this effect are unknown, and the physiological consequences of these studies remain to be established.
在本研究中，我们使用药理学方法评估了脑内血清素能神经元在抗利尿激素分泌调节中的可能作用。为实现这一目标，我们开发了一种特异且灵敏的抗利尿激素放射免疫分析法以及高度可重复的血浆提取方案。这些工具用于评估清醒大鼠对几种药理学刺激的血浆抗利尿激素反应。用血清素（5-羟色胺，5-HT）释放剂对氯苯丙胺处理导致血浆抗利尿激素浓度显著升高。下丘脑后部去传入神经（这将中脑的血清素细胞体与其在下丘脑的神经末梢分离）可阻断此效应。给予几种5-HT激动剂的分级剂量无作用。然而，用具有5-HT1 + 5-HT2活性的血清素激动剂MK212处理可诱导血浆抗利尿激素浓度显著升高。MK212对血浆抗利尿激素的作用可被选择性5-HT2受体阻断剂LY53857完全消除。这些研究证实并扩展了其他人的研究，后者为通过选择性5-HT2受体机制进行血清素能调节抗利尿激素分泌提供了药理学证据。血清素发挥此效应的具体神经解剖部位尚不清楚，这些研究的生理后果仍有待确定。
