乌司他丁对羊水栓塞大鼠肺部损伤的影响及机制

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10×104 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。

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

ObjectiveTo 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 (10×104 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. ResultsCompared 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). ConclusionUlinastatin 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.