Fundus striati vasopressin receptors in blood pressure control.
Kremarik, P., M. J. Freund-Mercier, and Q. J. Pittman.
Neuroscience Research Group, University of Calgary, Calgary,
Alberta, CANADA, T2N 4N1, Institut de Physiologie
G[acute]en[acute]erale, 21 rue R. Descartes, 67084 Strasbourg,
France
APStracts 2:0063R, 1995.
Vasopressin (VP), given intracerebrally to rats, can induce
antipyresis, motor disturbances and increases in arterial blood
pressure. The possibility that the VP-binding sites in the fundus
striati (FStr) could participate in these effects was investigated.
After a bilateral injection of 100pmol VP in the FStr, the fever
induced by an intraperitoneal injection of the lipopolysaccharide of
E. Coli (50[mu]g/kg) was not affected. Bilateral injections of
100pmol VP did not induce motor disturbances or alterations in body
temperature after either of two successive injections. In contrast,
bilateral injections of VP into urethane anesthetized rats induced
dose-dependent increases in arterial pressure without affecting heart
rate. This increase was blocked by a V1 antagonist; oxytocin and a V2
agonist were ineffective. In keeping with this preliminary
pharmacological analysis, radioligand binding studies of the FStr
revealed binding sites in the FStr exhibiting a binding profile
typical of the V1 subtype. This study suggests then that the V1
receptors in the FStr could participate in the central regulation of
the blood pressure.
Received 22 November 1994; accepted in final form 24 February
1995.
APS Manuscript Number R677-4.
Article publication pending Am. J. Physiol. (Regulatory Integrative
Comp. Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 10 March 1995.