The expressions of transforming growth factor-β1,thrombospondin-l and vascular endothelial growth factor in rat renal tissue in adenine-induced chronic renal failure

Objective:To study the expressions of transforming growth factor-β1 (TGF-β1),thrombospondin-1 (TSP-1) and vascular endothelial growth factor (VEGF) in rat renal tissue in adenine induced chronic renal failure (CRF).Methods:Sixty male SD rats were randomly divided into two groups:model group (n=30),2.5% Adenine solution was administered by gastric garage daily;control group (n=30),the same volume torch solution was administered by gastric garage daily.At the 7th,14th and 21th day,ten rats in every group were sacrificed.Urine sample,blood sample and kidney tissue were reserved.The body weight (BW),kidney weight/body weight index (KI),the levels of 24 hours urine protein (24 h U-TP),N-acety1-β-D-glucosaminidase (NAG) in urine sample,blood urea nitrogen (BUN),serum creatinine (SCr) and blood albumin (ALB) in blood sample were examined.The histological changes of kidney were observed by light microscopy,and the expressions of TGF-β1,TSP-1,VEGF were examined by immunohistochemistrical method.Results:At the 7th day,rat BW in model group was increased slowly than that in control group (P<0.01);ALB was no significant change in these two groups.At the 14th and 21th day,BW and ALB in model group were decreased clearly than those in the same group at 7th day (P<0.01);At 7th,14th and 21th day,the levels of 24 h U-TP,NAG,BUN and SCr in model group were progressively increased (P<0.01).And the expressions of TGF-β1 and TSP-1 were also progressively increased.In control group,VEGF was broadly expressed in renal tubular epithelial cells and podocytes.With the aggravation of pathological injury in renal tubulointerstitial tissue,VEGF expression was decreased in model group.In different times in model group,the expressions of TGF-β1 in renal tubulointerstitial tissue and tubule were positive correlation (r_s=0.940,P<0.01).The expression of VEGF in renal tubule was negative correlation with the expression of TGF-β1 in renal tubule (r_s=-0.945,P<0.01) and TSP-1 in renal tubulointerstitial tissue (r_s=-0.923,P<0.01).Conclusions:The increase of TSP-1-TGF-β1 axis expressions enhanced renal interstitial fibrosis and development,the TSP-1 may play an important role in adenine induced chronic renal failure;the decline of VEGF expression also led to renal interstitial fibrosis.