Adrenal and Plasma Corticosterone and Pituitary and Plasma ACTH in Alloxan Diabetic Rats 1 2

Abstract

Summary

Plasma and adrenal corticosterone as well as ACTH in both plasma and pituitaries of acutely diabetic rats were measured 72 hr after intraperitoneal injection of alloxan (20 mg/100 g). ACTH assays were performed in dexamethasone suppressed rats. A 50% increase in adrenal weights was associated with a 90% increase in total adrenal corticosterone and a 67% increase in adrenal corticosterone concentration. The high level of adrenal activity was associated with an equally high level of plasma corticosterone as well as plasma ACTH. The pituitary ACTH reserve remained unchanged. Experimental diabetes is associated with increased pituitary–adrenal activity without the depletion of the pituitary ACTH reserve. In the basal state of uncontrolled diabetes, ACTH synthesis is capable of keeping pace with the rate of ACTH release.