Characteristics of the receptors which mediate the stimulation of ACTH secretion by vasopressin in conscious dogs.
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 micrograms/dl (p less than 0.001). A specific antagonist of the vasoconstrictor activity of vasopressin, d(CH2)5MeTyrAVP (10 micrograms/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 micrograms/dl (p less than 0.005). In marked contrast, a selective antidiuretic (V2) 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 (V2) receptors.
D000305:Adrenal Cortex Hormones / Q000097:blood; D000324:Adrenocorticotropic Hormone / Q000378:metabolism*; D000818:Animals; D001127:Arginine Vasopressin / Q000494:pharmacology*; D003894:Deamino Arginine Vasopressin / Q000494:pharmacology; D004231:Diuresis / Q000187:drug effects; D004285:Dogs; D005260:Female; D008297:Male; D010121:Oxytocin / Q000031:analogs & derivatives / Q000494:pharmacology; D010902:Pituitary Gland / Q000187:drug effects / Q000502:physiology; D011945:Receptors, Angiotensin / Q000187:drug effects* / Q000502:physiology; D011956:Receptors, Cell Surface / Q000187:drug effects* / Q000502:physiology; D018019:Receptors, Corticotropin-Releasing Hormone; D017483:Receptors, Vasopressin; D014661:Vasoconstriction / Q000187:drug effects
D000305:Adrenal Cortex Hormones; D011945:Receptors, Angiotensin; D011956:Receptors, Cell Surface; D018019:Receptors, Corticotropin-Releasing Hormone; D017483:Receptors, Vasopressin; D001127:Arginine Vasopressin; C047063:oxytocin, Phe(2)-Orn(8)-; D010121:Oxytocin; D000324:Adrenocorticotropic Hormone; D003894:Deamino Arginine Vasopressin