Figure 2. Total PDE and PDE3 activities are decreased in SR microsomes isolated from PDE3A−/− hearts.
PDE activity in WT and PDE3A−/− cardiac SR fractions, expressed as (A) specific activity (pmol cAMP hydrolyzed/min/mg) or (B) a percentage of the total PDE activity in WT hearts. Total PDE activity was determined in 3 independent SR microsomal preparations using cilostamide to inhibit PDE3, rolipram to inhibit PDE4 and IBMX to inhibit total PDE activity. *p<0.001 vs WT, **p<0.05 vs WT total PDE activity.