Presence of two 3′–5′-cyclic AMP phosphodiesterases in rat kidney and frog bladder epithelial cells extracts

摘要: Abstract The phosphodiesterase activity extracted from frog bladder epithelial cells and rat kidney may be described as the sum of activities two phosphodiesterases (I II). Phosphodiesterases I II partially separated by gel filtration or centrifugation in sucrose gradients. Phosphodiesterase (molecular weight about 80,000) is stable on storage heat denaturation has a low affinity for cyclic AMP (Km 3 × 10−5 M). lower molecular (about 40,000) an ten times higher. It thermolabile more susceptible to inhibition ATP than I. possibility that correspond forms same enzyme discussed.