肿瘤坏死因子-α增强内皮素肾血管收缩作用的研究

目的 探讨肿瘤坏死因子-α(TNF-α)及肝素对内皮素-1(ET-1)收缩肾脏血管作用的影响,研究TN F-α在肝肾综合征发病机制中的作用。方法 应用离体灌注肾技术,恒量灌流正常大鼠的离体肾脏,在多导生理记录仪上连续记录肾脏灌注压力的改变,观察经TNF-α,肝素灌流90 min后,在ET-1刺激下,肾脏灌注压的改变。 结果 对照组,应用2 nmol/L ET-1刺激,可使灌注压上升(47±9)mm Hg;TNF-α(1 μg/L)处理组,基线压力无改变,应用2 nmol/L ET-1刺激,可使灌注压上升(97±36)mm Hg,与对照组比较差异有非常显著性,t=3.811,P<0.01;肝素(10 mg/L)处理组,基线压力无改变,应用2 nmol/L ET-1刺激,可使灌注压上升(11±6)mm Hg,与无肝素预灌流组[高出基础灌注压(30 ±6)mm Hg)]比较其灌注压升高幅度明显下降(t=9.41 4,P<0.01)。肾组织HE染色,3组均未见病理改变。 结论 TN F-α可能是通过增强三磷酸肌醇受体表达促进肾血管收缩,在肝肾综合征的发病机制中发挥重要作用。

Tumor necrosis factor- α enhances the effect of endothelin on renal vasoconstriction in isolated perfused rat kidney

OBJECTIVE: To explore the role of tumor necrosis factor-alpha (TNF-alpha) in the pathogenesis of hepatorenal syndrome. METHODS: By isolated perfused kidney technique, rat kidneys were perfused at a constant flow. Changes in perfusion pressure (mmHg) were consecutively measured with multi-functional physiology recorder. After TNF-alpha or heparin treated 90 minutes, the perfusion pressure stimulated by endothelin-1 (ET-1) was detected. RESULTS: TNF-alpha and heparin didn't modify the baseline perfusion pressure. When ET-1 was added at 2 nmol/L, the perfusion pressures increased to (47+/-9) mmHg, (97+/-36) mm Hg and (11+/-6) mm Hg in control, TNF-alpha and heparin (10mg/L) treated group, respectively, which were different among the three groups (t>or=3.811, P<0.01). No pathological damages were found in kidney tissues from all the groups after being stained with hematoxylin/eosin. CONCLUSION: TNF-alpha plays an important role in the pathogenesis of hepatorenal syndrome by promoting renal vasoconstriction.