EP300 and cardiac hypertrophy: Gusterson et al. [52] demonstrated that, while inhibition of p300 activity (using dominant negative mutant p300 that lacks CH1 domain) blocks cardiomyocyte hypertrophy induced by phenylephrine, a vasoconstrictor and an inducer of alpha 1 receptors, overexpression of wild-type p300 stimulates cardiomyocyte hypertrophy—clearly indicating the direct role of p300 activity in regulation of pathological cardiac hypertrophy [52].