title: Facilitatory role of central dopamine in the osmotic release of vasopressin.
abstract: In conscious rats, intracerebroventricular (i.c.v.) injection of the dopamine antagonist haloperidol (0.15 mumol) blocked increases in plasma vasopressin (AVP) and arterial pressure caused by i.c.v. administration of a hypertonic solution (990 mOsm/kg, 10 microliters), without affecting plasma osmolality, electrolytes or hematocrit. The application of the alpha-adrenergic antagonist phenoxybenzamine (0.15 mumol), however, did not significantly inhibit the responses of plasma AVP and arterial pressure to the hypertonic solution. We concluded that brain dopamine may play a facilitatory role in the osmotically stimulated AVP secretion.
authors.affiliation: Department of Physiology, Niigata University School of Medicine, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Yamaguchi
authors.forename: H
authors.initials: H
authors.lastname: Hama
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D004298:Dopamine / Q000502:physiology*; D006220:Haloperidol / Q000494:pharmacology*; D006982:Hypertonic Solutions / Q000494:pharmacology*; D007276:Injections, Intraventricular; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D014667:Vasopressins / Q000097:blood*; D014882:Water-Electrolyte Balance / Q000187:drug effects*
chemical_list: D006982:Hypertonic Solutions; D014667:Vasopressins; D006220:Haloperidol; D004298:Dopamine