NPPA and cardiac hypertrophy: To demonstrate the role of CaMKII in cardiac hypertrophy, H9C2 cardiomioblasts were incubated with adenoviral constructs encoding CaMKII catalytically inactive (CaMKII-DN), CaMKII wild-type (CaMKII-WT) or the empty virus as a negative control and then stimulated with PE for 24 h to assess ANP expression levels.