Abstract: Objective To observe the inhibitory role of Valproic acid (VPA) in hypertrophic cardiomycytes induced by angiotensin Ⅱ（AngⅡ）in rats. Method The cultured rat cardiomyocytes were divided randomly into the control group, the hypertrophic group and VPA group. They were treated with AngⅡ to induce hypertrophy and then given with VPA. The morphologic changes of cardiomyocytes were observed under the contrast phase microscope and electron microscope. The mRNA levels of β-MHC were exmained by Reverse transcriptase polymerase chain reaction (RT-PCR) method.The protein expressions of c-fos were exmanined by immunohistochemistry method. Result Stimulated by AngⅡ,the cardiomyocytes were enlarged under the contrast phase microscope and the ultrastructure also changed. After stimulated by AngⅡ,the mRNA level of β-MHC and the protein expression of c-fos increased in the hypertrophic cardiocytes. Given by VPA, these data decreased accordingly. Conclusion VPA may inhibit the cardiomyocyte hypertrophy induced by angiotensin Ⅱ in some degree.

Key words: Valproic acid, Angiotensin Ⅱ, Cardiomyocyte, Hypertrophy