González M C, Llorente E, Abreu P
Department of Physiology, School of Medicine, University of La Laguna, La Cuesta, Tenerife, Spain.
Neurosci Lett. 1998 Oct 2;254(3):133-6. doi: 10.1016/s0304-3940(98)00663-6.
Nitric oxide (NO) has been involved in the modulation of various neuroendocrine responses. This work is a study of dose-response and time-course of the effect of intracerebroventricular (i.c.v.) administration of (NO) generator sodium nitroprusside (SNP), on tyrosine hydroxylase (TH) activity of the median eminence (ME) and serum prolactin levels, performed on conscious male rats. SNP (1, 5 and 10 microg) inhibited the TH activity of the ME, 15 min following injection in a dose-dependent way, although the effect was only significant with the highest dose, and also increased in a dose-dependent manner the serum prolactin levels. Both actions were transient but vanished at different times following injection of 10 microg of SNP. These results suggest that NO, released from SNP, inhibits the tuberoinfundibular dopaminergic neurons of the basal hypothalamus to stimulate prolactin secretion.
一氧化氮（NO）参与了多种神经内分泌反应的调节。本研究旨在探讨在清醒雄性大鼠中，脑室内（i.c.v.）注射（NO）供体硝普钠（SNP）对正中隆起（ME）酪氨酸羟化酶（TH）活性及血清催乳素水平的剂量反应和时间进程。注射后15分钟，SNP（1、5和10微克）以剂量依赖的方式抑制ME的TH活性，尽管只有最高剂量的作用具有统计学意义，并且SNP还以剂量依赖的方式提高血清催乳素水平。这两种作用都是短暂的，但在注射10微克SNP后的不同时间消失。这些结果表明，SNP释放的NO抑制下丘脑基底核的结节漏斗多巴胺能神经元，从而刺激催乳素分泌。
