Expression and significance of thrombospondin-1 in renal tissues of rats with chronic allograft nephropathy

Objective To investigate the expression of TSP-1 in transplanted rat kidney and its relationship with CAN.Methods Fisher344 rat renal grafts were orthotopically transplanted into Lewis rats(CAN group), Lewis-to-Lewis kidney transplantations were also performed as the control group.16 weeks posttransplantation,the animals were sacrificed to harvest sera and renal allografts.The urinary albumin excretion and serum creatinine were measured and pathological changes assessed according to Banff 97 criteria.The expression of TSP-1 and TGF-β1 in renal tissues were observed by immunohistochemistry.Result Compared with the control group,CAN rats 24 h urinary protein,serum creatinine was significandy higher,the difference was statistically significant(P0.01). According to Banff 97 standard,no obvious pathological changes in the control group,and more than 24%glomerular sclerosis occurred in The CAN group.Renal function deteriorated progressively in the CAN group,and there was typical obvious tubular atrophy,interstitial fibrosis and severe intimal fibrosis observed in the kidneys.Banff score results of the two groups of renal transplantation were significant differences statistically significant(P0.01).In the control group,there was low expression of TSP-1 and TGF-β1,However there was high expression of TSP-1 and TGF-β1 and glomerular mesangial cells,renal tubular epithelial cells,renal interstitial cells were found in CAN group.Conclusion There was high expression of TSP-1 in renal tissues of rats with CAN,it suggests that TSP-1 plays an important role in the progression of CAN.