Wells T, Forsling M L
Department of Obstetrics and Gynaecology, UMDS, St Thomas's Hospital, London.
J Endocrinol. 1991 Jun;129(3):411-6. doi: 10.1677/joe.0.1290411.
A series of studies has been performed in the conscious rat to investigate the effect of the intracerebroventricular (i.c.v.) administration of the selective kappa-opioid receptor agonist, U50 488H, on arginine vasopressin (AVP) secretion stimulated by i.c.v. administration of hypertonic NaCl. Similarly, the effect of the i.c.v. administration of morphine and the i.v. administration of naloxone on AVP secretion was investigated. The response of AVP to an i.c.v. injection of hypertonic NaCl was potentiated by naloxone at a dose of 0.4 mg/kg, but a higher dose (1.2 mg/kg) was required to increase the basal plasma concentration of AVP. Prior treatment with U50 488H or morphine attenuated the increase in plasma concentrations of AVP stimulated by i.c.v. injection of hypertonic NaCl from 13.92 +/- 4.44 to 1.22 +/- 0.34 and 1.78 +/- 0.74 pmol/l respectively (n = 7; P less than 0.05). Prior administration of U50 488H also attenuated the potentiating effect of naloxone on AVP secretion stimulated by i.c.v. injection of hypertonic NaCl. These results indicate that basal AVP secretion is under tonic inhibitory control by dynorphin, and that mu- and kappa-opioid receptors mediate an inhibitory influence of endogenous opioids on osmoreceptor-mediated AVP secretion.
已经在清醒大鼠身上进行了一系列研究，以探讨脑室内（i.c.v.）注射选择性κ-阿片受体激动剂U50 488H对脑室内注射高渗氯化钠刺激的精氨酸加压素（AVP）分泌的影响。同样，研究了脑室内注射吗啡和静脉注射纳洛酮对AVP分泌的影响。纳洛酮以0.4mg/kg的剂量增强了AVP对脑室内注射高渗氯化钠的反应，但需要更高剂量（1.2mg/kg）才能提高AVP的基础血浆浓度。预先用U50 488H或吗啡处理可将脑室内注射高渗氯化钠刺激的AVP血浆浓度升高分别从13.92±4.44降至1.22±0.34和1.78±0.74pmol/l（n = 7；P<0.05）。预先给予U50 488H也减弱了纳洛酮对脑室内注射高渗氯化钠刺激的AVP分泌的增强作用。这些结果表明，基础AVP分泌受强啡肽的紧张性抑制控制，并且μ-和κ-阿片受体介导内源性阿片类物质对渗透压感受器介导的AVP分泌的抑制作用。
