在妊娠晚期大鼠中，视上核（SON）中的催产素神经元受到内源性阿片类物质的抑制。

Oxytocin neurones in the supraoptic nucleus (SON) are inhibited by endogenous opioids in late pregnant rats.

作者信息

Douglas A J, Johnstone L E, Neumann I, Leng G, Russell J A

机构信息

Dept. of Physiology, University Medical School, Edinburgh.

出版信息

Gene Ther. 1994;1 Suppl 1:S84.

PMID:8542430

Abstract

Late pregnant rats exhibit endogenous opioid restraint of oxytocin cells since i.v. naloxone (NLX opioid antagonist) increases oxytocin (OXT) secretion but OXT nerve terminals become desensitised to opioids. We have studied central opioid inhibition of OXT neurones in late pregnancy by measuring SON OXT neurones firing rate, immediate early gene (Fos) expression and dendritic OXT release under the influence of NLX On day 21 of pregnancy NLX strongly potentiated cholecystokinin (CCK) excitation of OXT neurones increased Fos protein expression and increased intranuclear release of OXT in the SON; NLX was ineffective in virgin rats. The data indicate central endogenous opioid inhibition of OXT neurone activity in late pregnancy which may restrain premature OXT release.

摘要

妊娠晚期大鼠表现出内源性阿片类物质对催产素细胞的抑制作用，因为静脉注射纳洛酮（阿片类拮抗剂）会增加催产素（OXT）的分泌，但OXT神经末梢对阿片类物质会产生脱敏作用。我们通过测量在纳洛酮影响下视上核（SON）中OXT神经元的放电频率、即刻早期基因（Fos）表达以及树突状OXT释放，研究了妊娠晚期中枢阿片类物质对OXT神经元的抑制作用。在妊娠第21天，纳洛酮强烈增强了胆囊收缩素（CCK）对OXT神经元的兴奋作用，增加了Fos蛋白表达，并增加了SON中OXT的核内释放；纳洛酮对未孕大鼠无效。数据表明，妊娠晚期中枢内源性阿片类物质对OXT神经元活动有抑制作用，这可能会抑制OXT的过早释放。