Development of Rat Liver Adenylcyclase

Abstract

A developmental study of rat liver adenylcyclase and of its sensitivity to stimulation by adrenalin, glucagon, and NaF was carried out. During the last days of prenatal development, basal activity and hormone or NaF stimulated activity rise. Maximal levels are reached between day 2 and 10 after birth. Thereafter, adrenalin-stimulated adenylcyclase activity decreases considerably. In relation to basal activity, glucagon (and NaF) sensitivity increases with age while adrenalin sensitivity is sharply reduced after 10 days of age. These results may be related to changes in specific enzyme inducibility and/or carbohydrate metabolism known to occur in the course of development of rat liver. Additive hormonal stimulation was only observed in preparations obtained from animals which were at least 30 days of age.