Plasma glucocorticosteroid and aldosterone levels during physiological and stress conditions in rabbits. II. adult animals.
The pattern of adrenal steroid secretion under basal and stress conditions and the response to tetracosactid (20.0 micrograms/kg body weight) were studied in adult male rabbits. In animals repeatedly stressed by artery puncture, plasma glucocorticosteroid levels were slightly higher than those found in unstressed control animals. The combined stress of repeated exposure to ether vapor for 60 sec, followed by artery puncture, significantly stimulated glucocorticosteroid release, concentrations progressively increasing with the number of ether exposures applied. A much faster and more pronounced stimulation of glucocorticosteroid release was seen in animals treated with 20.0 micrograms/kg body weight tetracosactid. Plasma aldosterone levels in animals stressed by artery puncture were higher, although not significantly, than those of unstressed control animals. Repeated exposure to ether vapor for 60 sec, followed by artery puncture, on the other hand slightly decreased plasma aldosterone concentrations. A strong stimulation of aldosterone release at 20--60 min after injection could be elicited only by intravenous administration of 20.0 micrograms/kg body weight tetracosactid. Because of the insensitivity of the zona glomerulosa cells to increased ACTH levels under stress conditions, it is concluded that ACTH is only of minor importance both under basal and stress conditions in the regulation of aldosterone secretion in the rabbit.
D000324:Adrenocorticotropic Hormone / Q000031:analogs & derivatives* / Q000378:metabolism / Q000502:physiology; D000375:Aging; D000450:Aldosterone / Q000097:blood; D000818:Animals; D003366:Cosyntropin / Q000494:pharmacology*; D005260:Female; D005938:Glucocorticoids / Q000097:blood*; D008297:Male; D011817:Rabbits; D013312:Stress, Physiological
D005938:Glucocorticoids; D003366:Cosyntropin; D000450:Aldosterone; D000324:Adrenocorticotropic Hormone