肠系膜淋巴管结扎对大鼠急性肺损伤的影响

目的：探讨结扎肠系膜淋巴管对失血-脂多糖（LPS）致大鼠急性肺损伤（ALI）的拮抗作用。方法：雄性Wistar大鼠45只，均分为结扎组、未结扎组、假手术组，以失血、LPS复制二次打击模型，结扎组行肠系膜淋巴管结扎术致肠淋巴液断流。在手术创伤后24 h，所有大鼠颈总动脉放血，进行血气分析；从左肺收集支气管肺泡灌洗液（BALF），观察WBC、NO及其合酶、SOD、MDA以及肺泡通透性指数等指标的水平；右肺制备10%组织匀浆，检测MPO、ATPase活性等指标；观察右肺后叶超微结构。结果：二次打击后，未结扎组动脉血PaCO2、BALF中细胞总数及PMN、NO2-/NO3-、NOS、MDA含量以及肺匀浆MPO活性、肺通透性指数均显著高于假手术组，动脉血pH、PaO2、BALF中SOD、肺匀浆ATPase活性显著低于假手术组（P<0.01，P<0.05）；结扎组大鼠BALF中细胞总数及PMN、MDA、NO2-/NO3-含量、肺通透性指数均显著高于假手术组，BALF中SOD活性显著低于假手术组（P<0.01，P<0.05）。但结扎组大鼠动脉血pH、PaO2、肺匀浆ATPase活性显著高于未结扎组，动脉血PaCO2、BALF中细胞总数及PMN、NO2-/NO3-、NOS、MDA含量、肺通透性指数及肺匀浆MPO显著低于未结扎组（P<0.01，P<0.05）；且肺血管内皮细胞损伤程度较未结扎组轻微。结论：肠系膜淋巴管结扎可减轻失血-LPS致大鼠的急性肺损伤。提示二次打击的肠系膜淋巴液在大鼠急性肺损伤的发病过程中发挥着重要作用。

Effect of mesenteric lymph duct ligation on actue lung injury in rats

AIM: To explore the effect of mesenteric lymph duct ligation against actue lung injury(ALI) in rats.METHODS: 45 Wistar rats were divided into three groups: the ligation group,the non-ligation group and sham operated group,and the two-hit model was established by hemorrhage and LPS injection.Mesenteric lymph was diverted by ligating mesenteric lymph duct in ligation group.All rats facilitated blood withdrawal for blood sample to arterial gas analysis after 24 hours.Then the WBC,NO,NOS,MDA,SOD and lung permeability index(LPI) were determined in bronchoalveolar lavage fluid(BALF),the MPO and ATPase activity were determined in lung homogenate.The ultrastructure was also observed.RESULTS: After two-hit,the PaCO_2,the total cells and PMN,the NO_2~-/NO_3~-,NOS and MDA content in BALF and MPO activity in lung homogenate and LPI in non-ligation group were significantly increased than those in sham operated group.PaO_2 and pH in arterial blood,SOD in BALF and the ATPase in lung homogenate were significantly lower(P<0.01 or P<0.05).The total cells and PMN,MDA,NO_2~-/NO_3~-in BALF,LPI in ligation group were significantly increased than those in sham operated group,and SOD in BALF was significantly lower(P<0.01 or P<0.05).The pH and PaO_2 in arterial blood,the ATPase in lung homogenate in ligation group were significantly increased than those in non-ligation group,and the PaCO_2,the total cells,PMN,NO_2~-/NO_3~-,NOS,MDA in BALF,LPI,and MPO in lung homogenate in ligation group were significantly lower than those in non-ligation group(P<0.01 or P<0.05).The injury of pulmonary vascular endothelium in ligation group was lighter than that in non-ligation group.CONCLUSION: The ligation of mesenteric lymph duct attenuates the ALI of rats.Mesenteric lymph might play an important role in the pathogenesis of ALI.