Abstract: AIM: To study the expression of transforming growth factor-β₁ (TGF-β₁) in the nephric tubule of spontaneous hypertensive rats and the relation of the TGF-β₁ and the renal tubulointerstitial fibrosis, and to investigate the effect of losartan on this expression and the protection effects of it on the kidney.METHODS: Same age male WKYs and SHRs were involved in this experiment.SHRs were divided into positive control (SHR-C) group and losartan treatment (SHR-L) group.The artenia pressure, renal function and β₂-MG of mice was monitored before and after experiment and the expression of TGF-β₁ in nephric tubule were measured by immuonohistochemitry assay.RESULTS: Compared with the WKY group, the contents of β₂-MG markedly increased in SHRC group (P<0.05) and decreased in SHR-L group (P<0.01), but the contrast of BUN and Scr not significance changed in both two groups (P>0.01).No or a few expression of TGF-β₁ occurred in WKY group.The expression of TGF-β₁ significantly increased in the positive control group with the progression of the hypertensive course, and meantime, the expression of TGF-β₁ significantly decreased in the losartan treatment group and the blood pressure also decreased.CONCLUSION: As the expression of TGF-β₁ intensively increased in hypertensive course, TGF-β₁ may be the important factor leaded to the renal tubulointerstitial fibrosis.Losartan has the effects on lowering blood pressure, reducing albuminuria, protecting renal function and delaying the renal tubulointerstitial fibrosis.

Key words: spontaneous hypertensive rat, transforming growth factor-β₁, nephric tubule, angiotensin receptor