Experimental Studies on Sodium Ferulate in Delaying Chronic Renal Failure in 5/6 Nephrectomized Rats

Objective To investigate sodium ferulate (SF) in delaying chronic renal failure (CRF) in 5/6 nephrectomized rats and to explore its mechanism. Methods Rats were randomly divided into pseudo-operation group,5/6 nephretomy group,sodium ferulate injection group (SFI group; 150 mg/kg), sodium ferulate gavage group (SFG group; 150 mg/kg) and Losartan gavage group (20 mg/kg). After operation,six rats in each group were killed in 4th ,8th and 12th weeks. After treatment, the level of serum creatinine and 24-hour urine protein were measured; glomerulosclerosis index (GSI) and the score of renal interstitial lesion were detected by HE staining; expression of endothelin 1 (ET-1),proliferative cell nuclear antigen ( PCNA) and α-smooth muscle actomyosin (α-SMA) were assayed by immunohistochemical staining method. The correlation between all the indexes was analysed.Results The levels of serum creatinine and urine protein,GSI,the score of renal interstitial lesion and the expression of PCNA and α-SMA were significantly higher in 5/6 nephretomy group than those in pseudo-operation group (P0.05),and the above indexes were decreased in SF groups compared with those in 5/6 nephrectomy group. A positive correlation was shown between GSI and the expression of α-SMA, PCNA and ET-1. Serum creatinine and 24-hour urine protein had a positive correlation with GSI and the expression of α-SMA , PCNA and ET-1; a positive correlation also existed between ET-1 expression and the expression ofα-SMA and PCNA.Conclusion SF has protective effect on 5/6 nephrectomized rats and its mechanism may be related to decreasing of serum levels of creatinine and urine protein, blocking myofibroblast generation and renal interstitial cell proliferation,and delaying glomerulosclerosis and renal interstitial fibrosis and inhibiting ET-1 expression.