Activity stain for the detection of cyclic nucleotide phosphodiesterase separated by polyacrylamide gel electrophoresis and its application to the cyclic nucleotide phosphodiesterase of beef heart

A rapid method for detecting cyclic 3′,5′-nucleotide phosphodiesterases in a gel matrix after electrophoresis has been described. The method can be employed for identifying cyclic nucleotide phosphodiesterase activity in partially purified preparations as well as for screening crude tissue extracts for this activity. When combined with density gel scanning, this technique permits the estimation of the relative levels of enzyme activity in different tissues or preparations. Beef heart contains at least two electrophoretically distinct forms of cyclic nucleotide phosphodiesterase activity, both of which can hydrolyze cyclic 3′,5′-AMP and cyclic 3′,5′-GMP.