Characteristics of the Receptors Which Mediate the Stimulation of ACTH Secretion by Vasopressin in Conscious DogsSchwartz J. · Reid I.A.
Department of Physiology, University of California, San Francisco, Calif., USA
In order to characterize the receptors which mediate the adrenocorticotropic hormone (ACTH) response to vasopressin in conscious animals, plasma 11-hydroxycorticosteroid concentration was measured in conscious dogs during the infusion of vasopressin or structural analogs of vasopressin which exhibit selective antidiuretic or vasoconstrictor activity. Vasopressin (1.0 ng/kg/min for 60 min) increased mean arterial pressure, decreased heart rate and increased plasma corticosteroid concentration from 1.0 ± 0.2 to 2.2 ± 0.2 µg/dl (p < 0.001). A specific antagonist of the vasoconstrictor activity of vasopressin, d(CH2)5MeTyrAVP (10 µg/kg), completely blocked the cardiovascular and corticosteroid responses to vasopressin. A selective vasoconstrictor (V1) agonist, PheOrnOT (1.0 ng/kg/min), which produced the same cardiovascular responses as vasopressin, increased plasma corticosteroid concentration from 1.1+0.1 to 2.9 ±0.9 µg/dl (p < 0.005). In marked contrast, a selective antidiuretic (V1) agonist, dDAVP (1.0 ng/kg/min) had no effect on blood pressure, heart rate or plasma corticosteroid concentration. These results indicate that the stimulation of ACTH release by vasopressin in conscious dogs is mediated by receptors which resemble vasoconstrictor-type (V1) receptors rather than antidiuretic-type (V<) receptors.
© 1986 S. Karger AG, Basel
Dr. Ian A. Reid, Department of Physiology, 762-S, University of California, San Francisco, CA 94143 (USA)
Received: November 13, 1984
Accepted after revision: February 21, 1985
Published online: April 01, 2008
Number of Print Pages : 4
Neuroendocrinology (International Journal for Basic and Clinical Studies on Neuroendocrine Relationships)
Vol. 42, No. 2, Year 1986 (Cover Date: 1986)
Journal Editor: Millar R.P. (Edinburgh)
ISSN: 0028–3835 (Print), eISSN: 1423–0194 (Online)
For additional information: http://www.karger.com/NEN