The effects of normal aging on cortisol and adrenocorticotropin responses to hypertonic saline infusion

• Published in: Psychoneuroendocrinology Vol. 20; no. 6; pp. 637 - 644
• Main Authors: Raskind, Murray A., Peskind, Elaine R., Pascualy, Marcella, Edland, Steven D., Dobie, Dorcas J., Murray, Sharon, Sikkema, Carl, Wilkinson, Charles W.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 1995; Elsevier
• Subjects: Adrenocorticotropic Hormone - blood; Adrenocorticotropin; Adult; Aged; Aging; Aging - physiology; Arginine Vasopressin - blood; Biological and medical sciences; Cortisol; Development. Metamorphosis. Moult. Ageing; Female; Fundamental and applied biological sciences. Psychology; Humans; Hydrocortisone - blood; Hyperosmolar; Hypothalamo-Hypophyseal System - drug effects; Hypothalamo-Hypophyseal System - physiology; Male; Middle Aged; Pituitary-Adrenal System - drug effects; Pituitary-Adrenal System - physiology; Reference Values; Saline Solution, Hypertonic; Single-Blind Method; Vasopressin; Vertebrates: anatomy and physiology, studies on body, several organs or systems; Water-Electrolyte Balance - drug effects; Water-Electrolyte Balance - physiology; Hyperosmolar; Aging; Cortisol; Adrenocorticotropin; Vasopressin; Human; Senescence; Hypothalamohypophysoadrenal axis; ACTH; Sodium chloride; Glucocorticoid; Neuropeptide; Hyperosmolarity; Blood plasma; Adenohypophyseal hormone; Adrenal hormone; Developmental stage; Hormonal investigation; Age
• ISSN: 0306-4530; 1873-3360
• DOI: 10.1016/0306-4530(95)00004-8

To assess the effects of aging on hypothalamic-pituitary-adrenal (HPA) axis responsivity, we compared the plasma cortisol and adrenocorticotropin (ACTH) responses to hypertonic saline infusion between normal older and young human volunteers. We administered a 90 min hypertonic saline infusion (5% sodium chloride at 0.06 ml/kg/min) and a 90 min placebo infusion (0.9% sodium chloride at 0.06 ml/kg/min) to normal young subjects ( n=13, age=29 ± 2 years) and normal older subjects ( n=8, age=63 ± 3 years). Plasma cortisol, ACTH, osmolality and arginine vasopressin (AVP) were measured before and at 30 min intervals during the infusions. The rate of increase in plasma osmotality and AVP induced by hypertonic saline infusion was similar between groups. The plasma cortisol increase during hypertonic saline infusion was greater in normal older subjects than in young subjects ( p=.03), but a stimulatory effect of hypertonic saline infusion on plasma ACTH was not apparent in either older or young subjects. These results suggest increased sensitivity with human aging to stimulation of cortisol release by hypertonic saline infusion at the adrenocortical level of the HPA axis.