The Expression Of Regulatory T Lymphocytes On Kidney In Sodium-sensitive Hypertensive Rats And Its Significance

[Objective] To investigate the expression of regulatory T lymphocytes on kidney in sodium-sensitive hypertensive rats and its significance.[Methods] Male Wistar rats were unilaterally nephrectomized, survived24rats were randomly divided into3groups (n=8,respectively):control group, hypertension group (model group), Mycophenolate Mofetil group (MMF group). Rat in control group drinking tap water, two other groups were administered desoxycorticosterone acetate(DOCA) subcutaneously (30mg/kg·week) or1%saline was added to their tap water. The model of sodium-sensitive hypertensive rats were induced when the blood pressure achieved140mmHg. After8weeks of follow-up, we monitored their blood pressure. We analysised24hour urinary protein (Upro) and the counts of Treg in the blood by flow cytometry and analysised the changes of IL-10in blood by ELISA; semi-quantitative analysis of renal pathology injury,the mRNA and protein expressions of Foxp3in renal tissue were detected by RT-PCR and Western blotting, respectively.[Results1Compared with control group,in the model group the Upro was significantly increased (25.88±4.3mg/24h vs11.92±2.11mg/24h,P<0.01), the percentage of CD4+CD25+Treg cells in CD4+T cells was lower (4.98%±0.62%vs12.72%±1.94%,P<0.01),the content of IL-10in serum decreased (294.57±14.56pg/ml vs458.32±19.39pg/ml,P<0.01), the damage of kidney tubule structure was more serious(3.89±0.51vs1.43±0.35,P<0.01), the mRNA Foxp3and protein expression of model rats kidney tissues were lower(1.03±0.15vs0.28±0.17,P<0.01;0.319±0.050vs0.973±0.238,P<0.01).Made a patch against model group,in the MMF group the Upro was decreased (12.39±2.23vs25.88±4.3mg/24h,±<0.01), the percentage of CD4+CD25+Treg cells in CD4+T cells was higher(6.80%±1.22%vs4.98%±0.62%,P<0.05), the content of MMF group increased (373.46±11.00vs294.57±14.56pg/ml,P<0.01), the damage of kidney tubule structure was reduced(2.47±0.37vs3.89±0.51,P<0.01), the Foxp3mRNA and protein expression in kidney tissues were higher (0.28±0.17vs0.73±0.15,P<0.01;0.319±0.050vs0.650±0.070,P<0.05).[Conclusion] Regulatory T cells participate the pathogenesis of the kidney injury in the sodium sensitive hypertension, and immune suppression could exert protection against hypertension-induced renal injury.