吸入一氧化氮对急性肺损伤小鼠肺组织炎症反应的影响

Effect of inhaled nitric oxide on pulmonary inflammatory response in mice with acute lung injury

目的 :探讨吸入一氧化氮 (NO)对内毒素〔即脂多糖 (L PS)〕诱导的急性肺损伤小鼠肺组织炎症反应的影响。方法 :利用腹腔内注射 L PS诱导小鼠急性肺损伤模型 ,按随机数字表法将动物分为 L PS组和 L PS+吸入 NO2 0× 10 - 6组。 L PS注射前 (0时 ,即正常对照 )及注射后 1、3、6和 12小时处死小鼠 (n=6 ) ,分别测定肺组织湿重 /干重 (W/D)比值 ,同时用迁移率改变电泳法 (EMSA)检测核因子κB(NFκB)的活性 ,用酶联免疫吸附法 (EL ISA )检测肿瘤坏死因子α(TNFα)和白介素 10 (IL 10 )的浓度 ,用逆转录聚合酶链反应(RT PCR)法检测 TNFα m RNA及 IL 10 m RNA的表达 ,并观察肺组织病理改变。结果 :L PS注射后 3、6、12小时 ,W/D分别为 4 .80± 0 .31、4 .82± 0 .10和 4 .6 3± 0 .18,明显高于正常对照 (3.6 7± 1.0 4 ,P均 <0 .0 5 )。吸入 2 0× 10 - 6 NO后 3和 12小时 ,W/D分别为 4 .0 4± 0 .77和 4 .2 4± 0 .75 ,显著低于 L PS组 (P均 <0 .0 5 )。吸入 NO2 0× 10 - 6 6小时后 ,小鼠肺组织核蛋白 NFκB活性为 2 5 0 .6± 5 1.5 ,明显低于 L PS组 (40 5 .7± 6 2 .4 ,P<0 .0 5 )。与 L PS组比较 ,吸入 NO后 3～ 12小时 ,肺组织匀浆中 TNFα和 IL 10浓度均明显降低。吸入 NO后 6小时 ,肺组织匀浆中

Objective:To investigate the effect of inhaled nitric oxide (NO) on pulmonary inflammatory response in mice with acute lung injury (ALI) induced by lipopolysaccharide (LPS).Methods:ALI murine model was induced by intraperitoneal injection of LPS and then randomly assigned to two groups (LPS,LPS + inhaled NO 20×10 -6 group).At before exposure(0 hour,as normal controls) and 1,3,6,and 12 hours after LPS exposure,lung wet/dry weight ratios (W/D) were recorded to assess lung injury.The total lung homogenates were prepared to detect nuclearκB(NFκB) activity by electrophoretic mobility gel shift assay (EMSA),tumor necrosis factorα (TNFα) and interleukin10 (IL10) levels by enzymelinked immunosorbent assay (ELISA) and their mRNA expression by reverse transcription polymerase chain reaction (RTPCR).Meanwhile,pathologic changes were examined.Results:After LPS injection,W/D was 4 80±0 31,4 82±0 10,and 4 63±0 18 respectively at 3,6,12 hours,which were higher than that prior to LPS challenge (3 67±1 04,all P <0 05) significantly.W/D ratio was 4 04±0 77 and 4 24±0 75 at 3,12 hours in inhaled NO 20×10 -6 group after LPS exposure,which were decreased markedly than LPS group.As compared with the NFκB activity in LPS group (405 7±62 4),NFκB activity decreased significantly (250 6±51 5) at 6 hours in inhaled NO 20×10 -6 group.The concentration of TNFα and IL10 were (197 1±52 4) ng/L and (126 0±40 1) ng/L at 6 hours in LPS group,which were decreased to (37 8± 6 1) ng/L and (21 7±11 1) ng/L respectively in inhaled NO 20×10 -6 group.As compared with LPS group,mRNA levels of TNFα and IL10 decreased in inhaled NO groups.Histologically,inhaled NO alleviated LPS induced lung injury,including alveolar hemorrhage and edema,and inflammatory cells infiltration.Conclusions:Inhaled NO 20×10 -6 ,which inhibited NFκB activation and downregulated inflammatory mediator expression in ALI mice,may be an effective approach for the treatment of ALI.