Impact of Prolonged Physical Training on the Pituitary Glucocorticoid Sensitivity Determined by Very Low Dose Intravenous Dexamethasone Suppression Test

Autor(es)

Silva, T. S. ^[1] ; Longui, C. A. ^[1] ; Faria, C. D. C. ^[1] ; Rocha, M. N. ^[1] ; Melo, M. R. ^[1] ; Faria, T. G. ^[2] ; de Souza e Almeida, J. A. ^[2] ; Hayashi, L. F. ^[3] ; Kater, C. E. ^[3]

Afiliação do(s) autor(es)

^[1] Santa Casa Sao Paulo Fac Med Sci, Dept Physiol, Mol Med Lab, Sao Paulo - Brazil

^[2] Brazilian AF Acad Pirassununga, Sao Paulo - Brazil

^[3] Univ Fed Sao Paulo, Lab Steroids, Div Endocrinol, Dept Med, Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Hormone and Metabolic Research; v. 40, n. 10, p. 718-721, OCT 2008.
• Citações Web of Science: 7

Resumo

The activity of the hypothalamic-pituitary-adrenal axis is usually modulated by several stress factors, including exercise. Different responses are induced by physical training according to duration and intensity of exercise. During prolonged training, cortisol remains normal or decreased as a consequence of altered cortisol secretion, metabolism and excretion, and possibly by changes in glucocorticoid sensitivity. The aim of this study was to evaluate the impact of prolonged physical training on the glucocorticoid sensitivity. Eighteen cadets of the Air Force Academy, mean (SD) age: 18.7 (1.0) years, underwent an intensive 6-week preparatory training-period considered adequate by inducing significant changes on body composition measured by bioelectrical impedance. Measurement of individual's pituitary glucocorticoid sensitivity was done by an intravenous very low dose dexamethasone suppression test (20 mu g/m(2)) that was performed before and after the training period. Cortisol levels were obtained at basal condition and 120 minutes after the dexamethasone infusion. Basal cortisol showed a significant decrease after prolonged training. The percent cortisol suppression after dexamethasone tended to be lower after the training period. Overall, our data suggest that prolonged physical training is able to reduce glucocorticoid sensitivity, which can have a beneficial impact in chronic stress conditions. (AU)

• Processo FAPESP: 04/03208-2 - Quantificação da expressão de receptores glicocorticóides por PCR em tempo real e sua correlação com a sensibilidade individual aos glicocorticóides
• Beneficiário: Carlos Alberto Longui
• Modalidade de apoio: Auxílio à Pesquisa - Regular