TY - JOUR
T1 - Spontaneous and glucocorticoid-inhibited adrenocorticotropic hormone and cortisol secretion are similar in healthy young and old men
AU - Waltman, Claire
AU - Blackman, Marc R.
AU - Chrousos, George P.
AU - Riemann, Christopher
AU - Harman, S. Mitchell
PY - 1991/9
Y1 - 1991/9
N2 - We investigated the effects of age on pituitaryadrenocortical function in healthy young (21–38 yr, n = 11) vs. old (66–78 yr, n = 11) men by drawing frequent serial basal blood samples from 2000-0800 h for measurement of ACTH and cortisol, followed by an iv ovine CRH (oCRH) stimulation test. Subjects were readmitted at intervals and given increasing doses of oral dexamethasone (0.15, 0.3, 0.6, 1 mg) at midnight, followed by repeat blood sampling from 0400–0800 h and oCRH testing. We compared mean hormone levels for the entire 12-h and three component 4-h periods of the basal visit, and for each 4-h dexamethasone visit using the Mann-Whitney U test and repeated measures analysis of variance. Pulsatile secretion was characterized using the Pulsar computer program. Basal mean 12-h and 4-h ACTH and cortisol values did not differ with age (P > 0.1). Pulse analysis revealed no age change in the corresponding values for peak frequency, amplitude, or duration for either hormone examined. Increasing doses of dexamethasone produced progressive inhibition of mean ACTH and cortisol levels (P < 0.001) as well as decreased (P < 0.01) pulse frequency, amplitude, and duration with no age differences (P > 0.1). ACTH and cortisol responses to oCRH were progressively suppressed by increasing doses of dexamethasone (P < 0.02) and did not differ between age groups (P > 0.3) except for a slightly higher peak cortisol response (P = 0.05) in the older men at the 0.3 mg dexamethasone dose. We conclude that basal and oCRH-stimulated ACTH and cortisol secretion, as well as sensitivity of the ACTH-cortisol axis to glucocorticoid feedback suppression, are essentially unaltered with age in healthy men.
AB - We investigated the effects of age on pituitaryadrenocortical function in healthy young (21–38 yr, n = 11) vs. old (66–78 yr, n = 11) men by drawing frequent serial basal blood samples from 2000-0800 h for measurement of ACTH and cortisol, followed by an iv ovine CRH (oCRH) stimulation test. Subjects were readmitted at intervals and given increasing doses of oral dexamethasone (0.15, 0.3, 0.6, 1 mg) at midnight, followed by repeat blood sampling from 0400–0800 h and oCRH testing. We compared mean hormone levels for the entire 12-h and three component 4-h periods of the basal visit, and for each 4-h dexamethasone visit using the Mann-Whitney U test and repeated measures analysis of variance. Pulsatile secretion was characterized using the Pulsar computer program. Basal mean 12-h and 4-h ACTH and cortisol values did not differ with age (P > 0.1). Pulse analysis revealed no age change in the corresponding values for peak frequency, amplitude, or duration for either hormone examined. Increasing doses of dexamethasone produced progressive inhibition of mean ACTH and cortisol levels (P < 0.001) as well as decreased (P < 0.01) pulse frequency, amplitude, and duration with no age differences (P > 0.1). ACTH and cortisol responses to oCRH were progressively suppressed by increasing doses of dexamethasone (P < 0.02) and did not differ between age groups (P > 0.3) except for a slightly higher peak cortisol response (P = 0.05) in the older men at the 0.3 mg dexamethasone dose. We conclude that basal and oCRH-stimulated ACTH and cortisol secretion, as well as sensitivity of the ACTH-cortisol axis to glucocorticoid feedback suppression, are essentially unaltered with age in healthy men.
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U2 - 10.1210/jcem-73-3-495
DO - 10.1210/jcem-73-3-495
M3 - Article
C2 - 1651956
AN - SCOPUS:0025955324
VL - 73
SP - 495
EP - 502
JO - Journal of Clinical Endocrinology and Metabolism
JF - Journal of Clinical Endocrinology and Metabolism
SN - 0021-972X
IS - 3
ER -