Effects of the hypothirodism treatment and of hyperthiroidism on the stress system activity

Abstract

Introduction: thyroid diseases are often observed in women, which induce many alterations including cardiovascular, osteomuscular and nervous systems. Thyroid hormones have an important influence on stress regulate system and suggest that thyroid dysfunctions might have a complicated modulation on the stress axis.

Patients and methods: aiming to observe the influence of hypo and hyperthyroi clinical conditions, before and after treatment in 7 hypothyroid, 7 hyperthyroid and 7 normal women as control group.

Measurements: we performed ACTH and Cortisol curve of secretion after stimulation with hCRH.

Results: ACTH response to hCRH was higher both in hypothyroid (849±93 p<0,05) and hyperthyroid (917±124 p<0,05) condition in relation to the control group (618±59,4 pmol/L/120 min). Low doses of thyroid hormone therapy reduced (632±83) ACTH the response to hCRH. However, higher doses of thyroid hormone in hypothyroid patients increased the response (947±146 pmol/L/120 min). These observations were correlated with cortisol responses. In hyperthyroid patients, basal ACTH secretion was higher during hyperthyroidism and so was the response to hCRH stimulation, which decreased after antithyroid therapy (591±77 pmol/L/120 min p<0.05).

Conclusions: hypo and hyperthyroid patients have ACTH hyper-response to hCRH that suggest a different levels of thyroid HPA control including an alteration in pituitary CRH receptor in hypothyroid patients and a modification of pituitary ACTH reserve in hyperthyroidism.