In mice with pressure overload-induced cardiac hypertrophy, sildenafil inhibited the decomposition of cGMP by PDE5 to improve myocardial PKG bioactivity, thus suppressing cardiac hypertrophy and interstitial fibrosis via the inactivation of the prohypertrophic signalling pathways [19, 70]. This evidence concerns the gene PRKG1 and cardiac hypertrophy.