INCREASED ADRENOCORTICOTROPHIC HORMONE IN THE SERA OF ACUTELY SCORBUTIC GUINEA-PIGS

Abstract

SUMMARY 1. In the Sayers test for adrenocorticotrophic hormone (ACTH), serum obtained from normal guinea-pigs was not active. Serum from guinea-pigs with severe scurvy caused ascorbic acid (AA) depletion and behaved as though it contained ACTH. The response increased with increasing dosage, and a valid assay was obtained with it and with authentic ACTH dissolved in serum from normal animals. Both normal serum and that from scorbutic animals sometimes possessed the property of increasing the slope of the response curve above that obtained for ACTH in saline. 2. 100 ml. of a sample of pooled sera from guinea-pigs with severe scurvy was estimated to possess the activity of 41 mU ACTH, but the fiducial limits were wide. 3. When guinea-pigs, given a small daily supplement of AA, were pair-fed with animals developing scurvy, no activity was detected in their sera. Activity was reduced and perhaps abolished in the sera of animals with acute scurvy by treatment in the terminal stages with AA, cortisol, cortisone or deoxycorticosterone acetate (DCA), but not with progesterone, oestradiol or testosterone. 4. During the development of scurvy the urinary 17-ketosteroids (KS) and 17-ketogenic steroids (KG) rose steadily, but in animals pair-fed with them and receiving a small supplement of AA each day, the increase in KS was less and KG showed little change.