An attempt to evaluate the steroidogenic activity of synthetic adrenocorticotropic peptides: the circulation method.

Abstract

Apparent differences between the time curves (as determined by a method designated as the circulation method) of corticosterone concentration in the adrenal venous blood in hypophysectomized rats followed by the administration of natural ACTH and synthetic adrenocorticotropic peptides were demonstrated. When the areas under the curves obtained for 2 or 3 different doses of various adrenocorticotropic preparations were assumed as the responses, parallel dose-response regression lines were obtained for all the peptides tested. The relative potencies computed form this dose-response relationship somewhat differed from those by the established methods. It is suggested that the circulation method may be useful in evaluating the adrenal-stimulating potency of various preparations for therapeutic purposes.