Adenyl cyclase and phosphodiesterase activity in cerebral cortex of normal and undernourished neonatal rats

Abstract

Adenyl cyclase and cyclic nucleotide phosphodiesterase were measured in homogenates of cerebral cortex from well-fed and undernourished rats at 3, 10, and 19 days after birth and in homogenates from normal adult rats. The specific activities of both enzymes increased progressively between 3 and 19 days postpartum, and were the same in cortical homogenates from well-fed and undernourished rats. In the adult, adenyl cyclase was approximately half the value observed at 19 days of age. Activities of adenyl cyclase in whole homogenates of cerebral cortices were, in part, dependent upon the presence of low concentrations of a soluble, heat stable cellular component.