Figure 3. Measurements of SR Ca2+ content (A) as well as PLN and RyR2 phosphorylation (B&C).
(A) INCX evoked by a 10s application of 20mM caffeine in the presence or absence of RpcAMPS or ROL (left). Mean (time) integrated INCX to assess SR Ca2+ content bottom (right). *P< 0.05 versus WT. (B) Representative Western blot of protein extracts from left ventricular cardiomyocytes to measure phosphorylated PLN (left). Average intensity ratios of pPLN/PLNtotal(right). *P< 0.05 versus WT; †P<0.05 vs. PDE4D−/− (n=5 hearts). (C) Representative WB of protein extracts from left ventricular cardiomyocytes illustrating the effect of PDE4D ablation on phosphorylated RyR2 (pRyR2) levels (left). Mean data showing changes in pRyR2/ RyR2total ratios in PDE4D−/− hearts (right). *P<0.05 versus PDE4D WT (n= 4 hearts).