Effects of tanshinone Ⅱ on the mRNA expression of c-fos、c-myc and c-jun in angiotensin Ⅱ-induced hypertrophy of cardiomyocytes / 中国药理学通报

ABSTRACT

Aim To investigate the effect of tanshinoneⅡA(TSN) on the hypertrophy induced by angiotensinⅡ(AngⅡ)in the primary culture of neonatal rat cardiomyocytes. Methods Cardiomyocytes of Wistar rats were cultured with pancreatin and preplating technique. The hypertrophy of cardiomyocytes was induced with angiotensinⅡ, and intervened with TanshinoneⅡA and Valsartan. The effect of TSN on cardiomyocytewas evaluated by 3-[4,5-dimethylthiazol-2-yl]-3,5-diphenylformazan (MTT) assay. As the index of cardiomyocyte hypertrophy, protein synthesis rate was measured by ~3H-Leucine incorporation and the cell size was determined by phase contrast microscope. The proto-oncogene c-fos、c-myc and c-jun mRNA expressions were assessed using reverse transcription polymerase chain reaction (RT-PCR). Results Exposure of cultured cardiomyocytes to TSN (5～80 ?mol?L~ -1 ) for 24 h produced marginal cytotoxicity. Additonally, myocyte monolayers continued to contract synchronously in the presence of TSN. With the treatment of cardiomyocytes by AngII for 7 days, the cell size of cardiomyocytes of the group of Ang Ⅱ(28.5?3.8) ?m increased more prominently than the group of control(19.8?1.9) ?m(P