THE DISCUSSION of therapy with adrenal steroid hormones dealt with fundamental concepts of steroid metabolism and the application of these principles to the treatment of various important diseases of pediatric interest. This summary is limited to the basic concepts of therapy with steroids because a discussion of theory is considered likely to be of more lasting value than a temporary summing-up of clinical results.
The human adrenal cortex secretes two main types of steroid hormones, the socalled mineralocorticoids and the glucocorticoids. The first is normally represented by aldosterone, the action of which is mimicked by the synthetic steroid, desoxycorticosterone. (DOCA stands for the acetate of desoxycorticosterone.) Aldosterone secretion appears to be regulated by changes in the volume of extracellular fluid of the body via an hypothalamic-pituitary mechanism. The actions of the mineralocorticoids are widespread but mainly concern the kidney and the sweat glands, leading to retention of sodium and, with it, of water in exchange for potassium. Deficiency of mineralocorticoid, as in Addison's disease, results in loss of sodium and water, accumulation of potassium, dehydration, hypotension, and ultimately renal failure and death.
Hydrocortisone is the predominant glucocorticoid normally secreted by the adrenal cortex in response to stress or injection of adrenocorticotropin(ACTH). It appears that the concentration of hydrocortisone in the blood regulates the amount of ACTH secreted by the anterior pituitary; as it decreases, the hypothalamus stimulates the pituitary to release more ACTH in an effort to raise it; conversely, as the concentration increases, the hypothalamus inhibits pituitary release of ACTH and the adrenal cortex becomes inactive.
- Copyright © 1957 by the American Academy of Pediatrics