Influence of Thyroid hormone on Adrenocortical Function

Abstract

The influence of thyroid hormone on secretory activity of adrenal cortex and cortisol metabolism was studied clinically and experimtntally.
Base levels of plasma cortisol were within normal range regardless of thyroid functions in 6 hyper-Rate of clearance of cortisol from the body was accelerated by thyroid hormone either in reduction and conjugation by human liver or in renal clearance of guinea pigs.
Hyperactivity of adrenal cortex in hyperthyroidism, and diminished adrenal activity in myxedema, seem to be an expression of feed back mechanism of anterior pituitary to maintain a constant plasma level of cortisol as suggested previouly by DiRaimondo, Peterson and other investigator. There was some evidence of exhaustion in secretory activity of adrenal cortex in hyperthyroidism due to over doses of ACTH stimulation.