Expressions of IGF-1 and TGF-β_1 at different stages of spontaneously hypertensive rats and their relationship with the left ventricular hypertrophy and myocardial fibrosis

Objective To investigate the expression of IGF-1 and TGF-β 1 at different stages of hypertension in the spontaneously hypertensive rats (SHR) and their relationship with ventricular hypertrophy and myocardial fibrosis in the left ventricle. Methods The expression of IGF-1 and TGF-β 1 mRNA were measured with RT-PCR. Dynamic changes of the left ventricular hypertrophy and myocardial fibrosis were examined by biochemical assay and image analysis. Results Increased expression of IGF-1 was observed from the 14 th to the 24 th week which coincided with the progress of the left ventricular hypertrophy (LVH), but not with that of myocardial fibrosis (MF). No significant change was observed in the expression of TGF-β 1 in SHR group when compared with that of control. Conclusion Increased expression of IGF-1 in the left ventricle of SHR is probably associated with the progress of LVH.