Stimulatory effect of intracerebroventricularly administered dopamine on vasopressin release in rats.
Experiments were designed to investigate the effects of the intracerebroventricular administration of dopamine (DA) and a DA antagonist (pimozide) on the immunoreactive-vasopressin (IR-VP) contents of the rat magnocellular nuclei (MCN), neurohypophysis (NH) and plasma. The IR-VP levels in the MCN and NH were decreased 5 min after administration of DA in a dose of 20 nmol, but that in the plasma was increased. This effect was not observed after pretreatment with pimozide. Administration of pimozide alone did not affect the IR-VP contents of the MCN, NH or plasma. The results suggest that DA given icv. has a stimulatory effect on VP release from the neurohypophysial system.
D000818:Animals; D001921:Brain / Q000187:drug effects / Q000378:metabolism*; D004298:Dopamine / Q000008:administration & dosage / Q000494:pharmacology*; D007276:Injections, Intraventricular; D008297:Male; D010868:Pimozide / Q000008:administration & dosage / Q000494:pharmacology; D010904:Pituitary Gland, Posterior / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D014667:Vasopressins / Q000097:blood / Q000378:metabolism*
D014667:Vasopressins; D010868:Pimozide; D004298:Dopamine