乌司他丁对羊水栓塞大鼠肺部损伤的影响及机制

Effect and mechanism of ulinastatin on pulmonary injury in rats with amniotic fluid embolism

目的探讨乌司他丁对羊水栓塞大鼠肺部损伤的影响及机制.方法取晚期妊娠SD雌鼠60只,实验分为3组,每组20只:对照组股静脉注入生理盐水;羊水栓塞组:股静脉按0.25 mL/100 g注入羊水胎粪液;乌司他丁组:在羊水栓塞组的基础上,腹腔注射乌司他丁10×10^4 U/kg.8 h后酶联免疫吸附试验(ELISA)测定支气管肺泡灌洗液(BALF)中肿瘤坏死因子-α(TNF-α)、白细胞介素(IL)-8、IL-1β及IL-6的含量.光镜分析小鼠肺组织病理及湿干比(W/D)变化.RT-PCR、Western blot检测大鼠肺组织中基质金属蛋白酶(MMP)-2、MMP-9表达情况.结果与对照组相比,羊水栓塞组肺泡灌洗液TNF-α、IL-8、IL-1β及IL-6明显升高(P<0.05),乌司他丁组以上指标较羊水栓塞组降低,差异有统计学意义(P<0.05).肺组织病理学显示:羊水栓塞组大鼠肺组织可见不同程度水肿,局部血管丰富,可见少量出血,支气管及血管的周围有大量炎症细胞浸润;乌司他丁组肺组织病理改变较羊水栓塞组减轻;对照组大鼠肺组织则无明显改变.与对照组相比,羊水栓塞组W/D值明显升高(P<0.05),乌司他丁组较羊水栓塞组降低,差异有统计学意义(P<0.05);羊水栓塞组肺组织MMP-2、MMP-9 mRNA和蛋白表达明显升高(P<0.05),乌司他丁组肺组织MMP-2、MMP-9 mRNA和蛋白表达较羊水栓塞组降低,差异有统计学意义(P<0.05).结论乌司他丁可能通过降低肺组织MMP-2、MMP-9表达水平,减轻炎症反应,对羊水栓塞后肺组织损伤有一定的保护作用.

Objective To investigate the effect and mechanism of ulinastatin on pulmonary injury in rats with amniotic fluid embolism. Methods Sixty SD female rats of late pregnancy were divided into 3 groups(n=20). The rats in control group were injected with normal saline via femoral vein;in amniotic fluid embolism group with amniotic fluid meconium fluid(0.25 mL/100 g);and in ulinastatin group with amniotic fluid plus intraperitoneal ulinastatin treatment(10×10^4 U/kg). The contents of TNF-α, IL-8, IL-1 β and IL-6 in BALF were determined by enzyme-linked immunosorbent assay(ELISA). The histopathology and W/D of lung tissue were analyzed by light microscopy. The expression of MMP-2 and MMP-9 was assessed by RT-PCR and Western blot. Results Compared with the control group, TNF-α, IL-8, IL-1β and IL-6 in the amniotic fluid embolism group were significantly higher(P<0.05);and those in the ulinastatin group were significantly lower than those in the amniotic fluid embolism group(P<0.05). Pulmonary histopathology showed that the pulmonary tissue of the rats in the amniotic fluid embolism group had different degrees of edema, rich blood vessels, a small amount of local bleeding, a large number of inflammatory cell infiltration around the blood vessels and bronchi;while the pathological change of the lung tissue in the ulinastatin group was less than that in the amniotic fluid embolism group;and the lung tissue of the rats in the control group had no significant change. Compared with the control group, the W/D value in the amniotic fluid embolism group was significantly higher(P<0.05), while that in the ulinastatin group was significantly lower(P<0.05). The gene and protein levels of MMP-2 and MMP-9 in the lung tissue of the amniotic fluid embolism group were significantly elevated than control group, while they were significantly alleviated ulinastatin(P<0.05). Conclusion Ulinastatin may reduce the expression level of MMP-2 and MMP-9 in the lung tissue, reduce the inflammatory response, and have a certain protective effect on the lung tissue injury after amniotic fluid embolism.