Response of Serum Corticosterone to ACTH and Stress in the Zinc-Deficient Rat 1

Abstract

Summary

The effect of zinc deficiency on in vivo synthesis and release of corticos-terone was examined under three conditions, stimulation by exogenous and two types of physiological stress. The serum concentrations of corticosterone were elevated by intraperitoneal injections of ACTH, but were not influenced by the zinc status of young male rats. Zinc-deficient male rats given an acute stress stimulus, exposure to diethyl ether vapors, responded with elevated levels of serum corticosterone that were not different from those of controls. Pregnant rats fed zinc-deficient diets throughout gestation and then subjected to an acute stress stimulus, surgery under anesthesia, after parturition had serum corticosterone concentrations 50% lower than control rats treated similarly. Zinc-deficient pregnant rats given zinc on the 19th day of gestation had corticosterone levels midway between the deficient and control rats. It was concluded that young zinc-deficient male rats respond with the normal release of corticosterone when challenged with exogenous ACTH or a simple physiological stress. Zinc-deficient female rats subjected to the severe stress of pregnancy, parturition, and surgery show a subnormal response.