HMGB1 and cardiac hypertrophy: As expected, we found that exogenous HMGB1 overexpression in myocardium by intramyocardially injection significantly enhanced pressure overload‐induced cardiac hypertrophy, while blockade of HMGB1 by HMGB1 box A tended to reverse the hypertrophy induced by pressure overload, which may be accounted for by the attenuation of local inflammation and relevant pathological changes.