PDE5A and heart failure: However, our data clearly show that we did not detect PDE5 expression in the LV samples of normal mice, mice with compensated hypertrophy or mice with heart failure (Fig. 1), as well as the RV and LV of young normal or the old hypertensive canines with diastolic dysfunction (Fig. 2), while PDE5 was detected in the lung samples used as a positive control and loaded on the same gel.