PDE3 is the major cGMP-PDE in adult mouse ventricular cardiomyocytes

Materials and methods We generated a transgenic mouse model with cardiomyocyte-specific expression of the highly sensitive fluorescence resonance energy transfer (FRET)-based cGMP biosensor red cGES-DE5. This sensor mouse allows us to performed FRET measurements of cGMP in freshly isolated adult mouse ventricular myocytes, to visulaize realtime dynamics of cGMP. To analyze cAMP and cGMP interactions (cGMP/cAMP signaling crosstalk), FRET experiments were performed in cardiomyocytes isolated from mice, transgenically expressing the FRET-based cAMP sensor Epac1-camps.