Quantitative Variations in the Adrenocortical Secretion of Dogs

Abstract

Adrenal venous blood of 17 dogs was collected under uniform conditions during periods of an hour or more for measurement of corticosteroid content and rate of blood flow. The steroids were fractionated by paper chromatography and estimated quantitatively. A minimum of five corticosteroids and three 17-ketosteroids were found in nearly all blood samples, but there was marked individual variation in the rate of secretion of each component. Since exogenous ACTH administration did not increase corticosteroid secretion significantly, it is concluded that conditions of the experiments provided maximal endogenous stimulation and that observed variations in steroid output indicate a wide range of corticosteroidogenic capacity in apparently healthy dogs.