THE RELATION BETWEEN ACTH AND INTERMEDINE

Abstract

The chromatophore-expanding-activity and the adrenal-ascorbic acid-, depleting activity of various ACTH and intermedin prepns. were compared. The 2 activities were correlated in the ACTH prepns., which were much more potent in melanophore expanding activity than were the intermedin prepns. Intermedin, however, did not affect adrenal ascorbic acid. Boiling ACTH with_N/10 NaOH destroyed ACTH activity but did not affect intermedin activity. Pregnancy urine contained melanophore-expanding activity but no ascorbic-acid-depleting activity. The melanophore effect of pregnancy urine was destroyed by heat and alkali, in contrast to the lack of effect on the melanophore activity of this treatment when applied to pituitary extracts. The authors think this is best explained by supposing that many types of pituitary hormones (and other materials as well) have melanophore expanding activity.