Objective:To investigate effects of 17β-estradiol(E2)on mechanical stretch-induced integrin β1/FAK/p38 MAPK signal pathway of cardiomyocyte hypertrophy. Methods:Cardiomyocyte from neonatal rats were cultured in vitro and cardiomyocyte hypertrophy was induced by mechanical stretch. The association of integrin β1 and FAK was evaluated by immunoprecipitation,and the phosphorylation of FAK and p38MAPK were determined by Western blot. Results:Mechanical stretch for 24 h significantly increased the association of integrin β1 and FAK,and increased the phosphorylation of FAK and p38MAPK. Pretreatment with 100 nmol/L E2 for 30 min significantly attenuated the increases in the association of integrin β1 and FAK which were attenuated by estrogen receptor antagonist ICI182780. Furthermore,E2 also decreased the levels of the phosphorylation of FAK and p38MAPK induced by mechanical stretch,which were also attenuated by ICI182780. Conclusion:The combination of E2 and estrogen receptors can inhibit the activation of integrin β1/FAK/p38MAPK signaling pathway induced by mechanical stretch to play a cardiovascular protective effect.