Species Differences in Circulating 17-Hydroxycorticosteroid Concentrations.

Abstract

Circulating 17-hydroxycorticosteroid concns. in various spp. were measured by the method of Nelson and Samuels. Adult human subjects, children and guinea pigs had mean concns. of 10.0, 10.9 and 33.1 [mu]g./100 ml. plasma resp. Negligible amts. were found in rats and none in rabbits. The latter failed to produce a measurable concn. of 17-hydroxy-corticosteroids following the admn. of ACTH, but was able to maintain high, prolonged levels of exogenously administered cortisone.