Role of somatostatin in the regulation of vasopressin secretion.
Intracerebroventricular (i.c.v.) administration of somatostatin-28 (SS-28) (30 ng-1 micrograms) resulted in a dose-dependent elevation of plasma concentrations of vasopressin. Continuous i.c.v. infusion of SS-28 produced a depletion of vasopressin-like immunoactivity within the paraventricular and supraoptic of the hypothalamus as determined by immunocytochemistry. To evaluate the role of endogenous brain somatostatin in the regulation of vasopressin secretion, animals were treated with cysteamine. Cysteamine (90 mg/kg) treatment given s.c. produced a 50% depletion of endogenous brain somatostatin-like peptide concentrations. Pretreatment of animals with cysteamine attenuated hemorrhage-induced elevation of plasma vasopressin levels. The elevation of plasma vasopressin concentrations following the i.v. administration of hypertonic saline or the i.c.v. administration of angiotensin-II were not altered by cysteamine treatment. These results are consistent with the conclusion that an endogenous brain somatostatin may be involved in the physiologic regulation of vasopressin secretion following hemorrhage.
D000818:Animals; D002543:Cerebral Hemorrhage / Q000378:metabolism; D003543:Cysteamine / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D007031:Hypothalamus / Q000187:drug effects / Q000378:metabolism*; D007276:Injections, Intraventricular; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D013004:Somatostatin / Q000494:pharmacology* / Q000502:physiology*; D053561:Somatostatin-28; D014667:Vasopressins / Q000378:metabolism*
D014667:Vasopressins; D013004:Somatostatin; D003543:Cysteamine; D053561:Somatostatin-28