Expression of connective tissue growth factor in the cardiomyocytes and the effect of TGF-β_1 on its secretion

AIM:To investigate the mRNA and protein expressions of connective tissue growth factor(CTGF) in the cardiomyocytes,and to evaluate the effect of transforming growth factor-β1(TGF-β1) on it.METHODS:Ventricular cardiomyocytes were isolated from neonatal rats and cultured for 48 h,then the cardiomyocytes were sorted by means of fluorescence-activated cell sorting(FACS).The sorted cells were continuously cultured for 48 h and divided into two groups:the control group and the TGF-β1 stimulation group.The mRNA expressions of CTGF,TGF-β1,and fibronectin(FN) were measured by reverse transcription-polymerase chain reaction(RT-PCR).Meanwhile,the expressions of CTGF and FN in the plasmosin were detected by Western blotting.RESULTS:There was basal expression of CTGF in the control group.After stimulation with TGF-β1,the mRNA and protein expressions of CTGF were remarkably increased by 2.49-folds and 3.63-folds(P0.01) and the mRNA and protein expressions of FN were increased by 1-fold and 4.18-folds(P0.01),respectively,compared with the control group.However,the mRNA expression of TGF-β1 was decreased by 34%(P0.01).CONCLUSION:Some fundamental secretion of CTGF in the cardiomyocytes and TGF-β1 may induce its expression significantly.The cardiomyocytes participate actively in the progress of the myocardial fibrosis.