吗啡对阿扑吗啡和催产素诱导的阴茎勃起及打哈欠的预防作用：大脑中的作用位点

Prevention by morphine of apomorphine- and oxytocin-induced penile erection and yawning: site of action in the brain.

作者信息

Melis M R, Stancampiano R, Gessa G L, Argiolas A

机构信息

B.B. Brodie Department of Neurosciences, University of Cagliari, Italy.

出版信息

Neuropsychopharmacology. 1992 Jan;6(1):17-21.

PMID:1315136

Abstract

The effect of morphine administered systemically or into the paraventricular nucleus of the hypothalamus (PVN) on penile erection and yawning induced either by oxytocin or by the dopaminergic agonist apomorphine was studied in male rats. Systemic morphine (0.5 to 5 mg/kg intraperitoneally [IP]) prevented in a dose-dependent manner penile erection and yawning induced by the intracerebroventricular injection (ICV) of oxytocin (30 ng) or by the subcutaneous (SC) administration of apomorphine (80 micrograms/kg). Morphine (0.1 to 5 micrograms), but not U-69,593 (5 micrograms), injected into the PVN 10 minutes before oxytocin or apomorphine, was found to be able to prevent penile erection and yawning induced by the unilateral PVN microinjection of oxytocin (10 ng) or apomorphine (50 ng). The morphine-induced prevention of these behavioral responses was abolished by pretreatment with naloxone (3 mg/kg IP) 15 minutes before morphine. The present results suggest that morphine prevents apomorphine- and oxytocin-induced penile erection and yawning by inhibiting the activity of oxytocinergic neurons through mu-type receptors in this hypothalamic nucleus.

摘要

在雄性大鼠中，研究了全身给药或向下丘脑室旁核（PVN）注射吗啡对由催产素或多巴胺能激动剂阿扑吗啡诱导的阴茎勃起和打哈欠的影响。全身注射吗啡（腹腔注射[IP]，0.5至5mg/kg）以剂量依赖的方式抑制了由脑室内注射（ICV）催产素（30ng）或皮下注射（SC）阿扑吗啡（80μg/kg）诱导的阴茎勃起和打哈欠。在催产素或阿扑吗啡注射前10分钟，向PVN注射吗啡（0.1至5μg），而非U-69,593（5μg），能够抑制由单侧PVN微量注射催产素（10ng）或阿扑吗啡（50ng）诱导的阴茎勃起和打哈欠。在吗啡注射前15分钟用纳洛酮（3mg/kg IP）预处理可消除吗啡诱导的对这些行为反应的抑制作用。目前的结果表明，吗啡通过该下丘脑核团中的μ型受体抑制催产素能神经元的活性，从而抑制阿扑吗啡和催产素诱导的阴茎勃起和打哈欠。