In vivo regulation of adrenocorticotrophin secretion in the immature ovine fetus. Modulation by ovine corticotrophin releasing hormone and arginine vasopressin.
RJ MacIsaac, M Congiu, M Levidiotis, JG McDougall, EM Wintour
J Dev Physiol | Published : 1989
This study investigates the in vivo regulation of ACTH secretion in the immature ovine fetus by AVP and oCRH. Previously we have demonstrated that whilst AVP-containing neurones are present from 42 days, oCRH-containing neurones cannot be detected in the fetal paraventricular nucleus or median eminence until after 90 or 100 days respectively. In acutely exteriorized fetuses aged between 64-90 days (n = 5), a haemorrhagic stress elicited a significant increase (P less than 0.01) in ACTH values. There was also a significant correlation between plasma ACTH and AVP concentrations in these fetuses. In chronically cannulated fetuses less than 100 days (n = 6) injection of AVP (200 ng) significantl..View full abstract