Hyperglycemia and Increased Liver Glycogen Values in Hypo-physectomized Rats on Chronic Administration of Adrenocorticotropic Hormone. ∗

Previous work from this laboratory has shown that the injection of small amounts of suitable anterior lobe extracts into 24-hour fasted hypophysectomized rats prevents the abnormal fall of muscle glycogen without affecting the blood glucose or liver glycogen. 1 To produce this effect the extract is given only during the fasting period, and the presence of the adrenals is not necessary. Further investigation has shown that this acute effect is not due to adrenocorticotropic hormone. 2 The present investigation is concerned with the effects of more chronic injection of adrenocorticotropic hormone. The extracts were prepared according to the method of Lyons, 3 and all chemical and operative procedures were carried out as reported previously. 1

In Table I are summarized various experiments dealing with 10-24 days injection of BA-2 (adrenocorticotropic hormone) and a purified lactogenic preparation. For the sake of convenience these experiments are called maintenance (injections started immediately after hypophysectomy) or repair (injections started 10-12 days; after hypophysectomy). All extracts were injected 3 times during the fasting period in addition to the previous treatment. These data show that after longer treatment with adrenocorticotropic hormone there is a significant increase in liver glycogen and blood glucose. Not only are these values higher than those of the untreated hypophysectomized rat, but they are also far higher than those found in untreated normal rats. The adrenals of the maintenance group were much larger than those of the repair group, an average of 32.5 mg. as compared with 22 mg. These values should be compared with 25 mg. for untreated normal rats, and 10 mg. for untreated hypophysectomized rats. The only known contamination of BA-2 was one unit of lactogenic hormone per mg.