Correlation Between Endostatin Expression And Tubulointerstitial Microvascular Lesions In Kidney From Unilateral Ureteral Obstruction Young Rats

Objective: To observe the trend, relevance and potential pathologic significance role of endostatin (ENS), vascular endothelial growth factor (VEGF) and CD31 in the course of tubulointerstitial microvascular lesions during in kidneys of young rats with unilateral ureteral obstruction (UUO), and the interfering effects with atorvastatin.Methods: Young SD male rats with unilateral ureteral obstruction (UUO) were served as experiment models. All of the rats were randomly divided into three groups, that was untreated group after UUO (UUO group, n=24), treated group after UUO (UUO+ATO group, n=24), and sham operation group (control group, n=24). At the time points that treated for 1, 3, 7, 14 days, six rats were sacrificed in each group and the left renal tissues were obtained to evaluate the renal tissues morphologic changes through HE and Masson staining, at the same time we detected the protein expression of ENS, VEGF, and CD31 in tubulointerstitial by immunohistochemistry. Finally, we evaluated the correlation among ENS, VEGF, and CD31 protein expression in localization and time phase. All the data of experiment were analyzed by statistics software SPSS16.0.Results: (1) Morphological changes: At day 3, dilated tubule, infiltrated into renal tissues of slight inflammatory cells, and swelling of tubular epithelial cells were observed in untreated group after UUO. It was showed obviously at day 7, such as, more tubule were dilated; generous inflammatory cells infiltrated into renal tissue, especially in tubulointerstitial regions; cellulose exudation and tubulointerstitial area broaden. With the experimental session continuing, untreated group after UUO compared with control group, there were significant differences in different time points (days1, 3, 7and14). The extent of tubulointerstitial pathological changes in treated group after UUO is more alleviative than the UUO group (P<0.01), but still more serious than the control group (P<0.01). (2) Expression of ENS, VEGF and CD31:â‘ Immunohistochemical staining indicated that ENS was expressed slightly in glomerular epithelial cellular and peritubular capillary of control group, and almost no exist in tubulointerstitial regions. VEGF was widely expressed in glomerular epithelial cells, tubular epithelial cells and podocytes. There was no difference in all the time points (P>0.05). CD31 widely expressed in glomerular endothelial cells and peritubular capillary endothelial cells, There was no difference in all the time points (P>0.05).â‘¡Compared with control group, the expression level of ENS was increased gradually, in tubule epithelial cellular, also in tubulointerstitial regions, it peaked at day 7 in tubulointerstitial regions, and slight decrease was observed at day 14, obviously higher than the control group. The expression level of VEGF and CD31 were decreased gradually ,with the experimental session continuing it becoming less and less.â‘¢The significant difference were observed between treated and untreated groups in different time points (P<0.01). (3) Correlation analysis: Negative correlations were observed among ENS and VEGF, ENS and CD31. Positive correlation was observed among VEGF and CD31.Conclusion: In the course of tubulointerstitial microvascular lesions with young rats, the up-regulated ENS exhibit a great sense, while the atorvastatin treatment has a visible interfering effects.