Effects of TGF-β1 and signal protein Smad3 on rat cardiac myocyte hypertrophy

AIM: To investigate the effects of TGF-β1 and signal protein Smad3 on rat cardiac myocyte hypertrophy. METHODS: The total protein was analyzed by flow cytometry and the ANF mRNA expression was measured by RT-PCR to judge the hypertrophy of cultured neonatal cardiac myocytes. Smad3 mRNA expression in cardiac myocytes was measured by RT-PCR, and the protein expression of Smad3 was analyzed by Western blotting. RESULTS: TGF-β1 significantly increased the total protein in cardiac myocytes and promoted ANF mRNA expression, compared with control group. In cultured neonatal myocytes, AS-ODN of Smad3 inhibited myocyte hypertrophy induced by TGF-β1. Smad3 mRNA and protein expression increased at 15 min after incubated with TGF-β1, reached the peak at 1 h, and declined at 4 h. CONCLUSION: TGF-β1 and signal protein Smad3 may participate in the progress of rat cardiac myocyte hypertrophy.