Marked reduction of cyclic GMP phosphodiesterase activity in virally transformed mouse fibroblasts

Abstract

Dibutyryl cAMP induced the accumulation of both cAMP phosphodiesterase and cGMP phosphodiesterase in normal mouse fibroblast (3T3) and transformed fibroblast (3T3-SV 40). The increase was larger with cAMP phosphodiesterase. Although both enzyme activities were reduced in the transformed cells, the reduction of cGMP phosphodiesterase was more pronounced. The differential increase of cAMP phosphodiesterase by B 2 cAMP and the disparate reduction of cGMP phosphodiesterase in the transformed cell suggest that the two enzymes are regulated separately.