Centrally administered vasopressin modifies stress hormone (cortisol, prolactin) secretion in sheep under basal conditions, during restraint and following intravenous corticotrophin-releasing hormone.
The effects of central (lateral ventricle) injections of vasopressin (2.5, 25 or 250 ng) on cortisol and prolactin release were investigated in castrated male sheep (N = 6) under basal (non-stress) conditions, during 120min of physical restraint and following peripheral injection of ovine corticotrophin-releasing hormone (oCRH). Cortisol and prolactin concentrations in non-stressed sheep were raised significantly (p < 0.05) in the 120 min following administration of 250 ng of vasopressin. The prolactin response to restraint stress was decreased (p < 0.05) in the 30-min period following central injection of 250 ng of vasopressin. The stimulatory effect of oCRH on cortisol release was enhanced (p < 0.05) by vasopressin (25 and 250 ng), whereas prolactin levels decreased (p < 0.02) in the 30-min period following injection of the highest dose of vasopressin. None of the central doses of vasopressin significantly altered plasma levels of this hormone, although vasopressin secretion was increased during restraint.
Matthews
S G
SG
AFRC Institute of Animal Physiology and Genetics Research, Cambridge Research Station, UK.
Parrott
R F
RF
D000818:Animals; D003346:Corticotropin-Releasing Hormone / Q000008:administration & dosage* / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D013006:Growth Hormone / Q000097:blood; D006854:Hydrocortisone / Q000097:blood*; D007103:Immobilization; D007275:Injections, Intravenous; D007276:Injections, Intraventricular; D008297:Male; D011388:Prolactin / Q000097:blood*; D012756:Sheep / Q000378:metabolism* / Q000502:physiology; D013997:Time Factors; D014667:Vasopressins / Q000008:administration & dosage* / Q000494:pharmacology
D014667:Vasopressins; D011388:Prolactin; D013006:Growth Hormone; D003346:Corticotropin-Releasing Hormone; D006854:Hydrocortisone