[Regulation of the activity of 3', 5'-cyclic AMP phosphodiesterase by pancreatic hormones].

The character of the insulin effect on the activity of phosphodiesterase (PDE) cAMP of various subcellular localization was studied in the liver of normal and diabetic rats. As a result of kinetic investigations for PDE cAMP preparations of the plasma membranes there were obtained kinetic characteristics of two PDE forms, differing by their affinity to the substrate. For the both PDE cAMP forms stimulation of the activity with insulin was indicated. In examining the insulin effect on the activity of PDE cAMP of the liver of rats with streptozotocin-induced diabetes there was revealed a significant effect of the hormone on the kinetics of the enzyme with a high affinity to cAMP only.