Effects of single and repeated doses of reserpine on the secretion of adrenocorticotrophic hormone.

The effects of single and repeated doses of reserpine on the secretion of adrenocorticotrophic hormone (ACTH) were studied in rats by determining changes in the adrenal and plasma concentrations of corticosterone, in the adrenal ascorbic acid levels, and in the adrenal gland weights. Treatment with doses of reserpine which induced sedation caused prolonged hypersecretion of ACTH. Such treatment did not impair the release of ACTH in response to a stressful stimulus as recorded by an increase in the plasma corticosterone even when there was no concomitant depletion in the adrenal ascorbic acid. This finding casts doubt on the value of the adrenal ascorbic acid determination as an index of ACTH secretion.