Basal Hypothalamo-Pituitary-Adrenal Axis Activity and Corticotropin Feedback in Young and Older Men: Relationships to Magnetic Resonance Imaging-Derived Hippocampus and Cingulate Gyrus Volumes
- 1 April 2002
- journal article
- clinical trial
- Published by S. Karger AG in Neuroendocrinology
- Vol. 75 (4), 241-249
- https://doi.org/10.1159/000054715
Abstract
Alterations in basal cortisol secretion and feedback sensitivity are reported in aging. However, it is not known whether these hypothalamus-pituitary-adrenal (HPA) axis alterations are related to structural brain changes. This study was designed to investigate these relationships in the human. Nine young (24.0 ± 1.2 years; mean ± SE; range: 19–30) and 11 older (69.0 ± 1.8 years; range: 59–76) men, in addition to having standardized magnetic resonance imaging of their brains, were given 0.5 mg/kg cortisol or placebo intravenously in a double-blind, crossover study. As expected, older men had significantly smaller volumes for all brain regions. Although the groups did not differ in baseline HPA axis activity, there were significant and specific relationships between the brain volumes and the baseline measures of HPA activity. Namely, for young and older subjects combined and after controlling for age and cerebral vault size, hippocampal volumes were inversely associated with 24-hour urinary cortisol and basal corticotropin (ACTH) levels, and the anterior cingulate gyrus volume was negatively correlated with baseline ACTH. Elderly subjects had a slower decrease in ACTH levels (percent of baseline level) during the first 30 min after cortisol administration. However, no associations were observed between the ACTH feedback indices and any brain measure. This report, although based on a small number of subjects, supports previous studies showing a blunted ACTH fast feedback during normal aging. Hippocampal atrophy appears to be related to increased basal measures of HPA axis activity, but not to fast ACTH feedback. It remains possible that age-associated changes in fast feedback may be related to changes to other brain sites, such as hypothalamus or pituitary.Keywords
This publication has 12 references indexed in Scilit:
- Cortisol differentially affects memory in young and elderly men.Behavioral Neuroscience, 2001
- Visualisation and quantification of rates of atrophy in Alzheimer's diseaseThe Lancet, 1996
- Effects of gender and age on the levels and circadian rhythmicity of plasma cortisolJournal of Clinical Endocrinology & Metabolism, 1996
- Cortisol suppression by dexamethasone in the healthy elderly: Effects of age, dexamethasone levels, and cognitive functionBiological Psychiatry, 1994
- Hippocampal formation volume, memory dysfunction, and cortisol levels in patients with Cushing's syndromeBiological Psychiatry, 1992
- In vivo assessment of pituitary volume with magnetic resonance imaging and systematic stereology: Relationship to dexamethasone suppression test results in patientsPsychiatry Research, 1992
- Do glucocorticoid concentrations rise with age in the rat?Neurobiology of Aging, 1992
- The supraoptic and paraventricular nuclei of the human hypothalamus in relation to sex, age and Alzheimer's diseaseNeurobiology of Aging, 1990
- Age and gender effects on the diagnostic power of the DSTJournal of Affective Disorders, 1987
- [3H]Dexamethasone binding in rat frontal cortexBrain Research, 1985