Influence of Adrenotropic Hormone Fractions on ‘Adrenal Repair’ and on Adrenal Ascorbic Acid

Abstract

WE have studied¹ the activity of pituitary extracts in the Sayers test², which depends on ability to induce a rapid fall in the ascorbic acid content of the adrenal glands of hypophysectomized rats, and in an adrenal ‘repair’ test based on the increase in the adrenal weight of the rat hypophysectomized one to three weeks previously and given three intraperitoneal injections daily of pituitary extract for three days, the animal being killed on the fourth day. Since an adrenal weight-increasing effect (AW effect) does not necessarily measure only changes in the weight of active cortical tissue, such an effect is necessarily less precisely defined than an ascorbic acid reducing effect (AA effect). In our investigation of these two activities of different pituitary extracts, we have adopted as our standard for the ratio AW/AA the pig pituitary preparation 84–85 U, kindly supplied by Armour Laboratories, Ltd.; this preparation is about 2.5 times as active in the ascorbic acid reduction test as the Armour standard preparation La-1-A, the provisional International Standard. We have followed three main lines of investigation, which it will be convenient to consider separately.