Objective To invesligale the effecl of Lhe cholinergic anli-inflammatory palhway(CAP) on the acule lung injury(ALI) induced by oleic acid and lipopolysaccharide in rals. Methods Twenly-four male Wislar rals were randomly divided into four groups(n = 6). ①Conlrol group: saline, 10 mL·kg-1, intraperitoneally,②ALI group: oleic acid was adminislraled with 0.15 mL · Kg"1 inlravenously 30 min aflerinlraperitoneal injeclion of lipopolysaccharide (LPS) with 10 mg·kg-1, ③stimulation (ST) group: electrical slimulalion( 5V, 2 ms, lHz) of Lhe righl cervical vagus nerve for 10 min before and after LPS and OA administration, ④ tetrahydroaminoacridine ( THA) group: tetrahydroaminoacridine was given at 1.5 mg · Kg~ intravenously before LPS and OA administration. Btood and tissue samples were collected 130 minutes after the first drug injection in all groups. TLR2 and TLR4 mRNA, NF-KBp65 , MPO of lung tissue and IL-6 of serum were measured respectively. The btood gas analysis, wet weight to dry weight ratio ( W/ D) of right lung, and pathotogical changes were also observed.Results As compared with group C, the pH and PaO2 decreasedmarkedly in group ALI while the histopathotogic changes of lung tissue showed alveolar hemorrhage, necrosis and proteinaceous alveolar edema. W/D ratio, the activity of MPO, NF-kB expression and the level of serum IL-6 significantly increased. As compared with group C, the expressions of the TLR2 and TLR4 mRNA were markedly increased in other three groups, but no significant change was found among these three groups. As compared with group ALI, pH and PaO2 markedly increased in group ST and group THA as well as PaCO2 decreased. The lung tissue showed slight pathotogical changes. W/D ratio and the activity of MPO were significantly reduced. The expression of NF-kB p65 protein and the amount of serum IL-6 markedly decreased. Conclusions Electrical slimulalion of the vagus nerve or adminislralion of THA intravenously could prolecl the lung againsl ALI induced by LPS and OA via aclivaling cholinergic anli-inflammatory palhway; the CAP can inhibil the aclivalion of NF-kB and reduce the production of proinflammatory cytokine but had no effecl on the expression of TLRs.%目的 研究胆碱能抗炎通路(cholinergic anti-inflammatory pathway,CAP)对内毒素复合油酸2次打击致大鼠急性肺损伤(acute lung injury,ALI)的影响及其可能的作用机制.方法 24只雄性Wistar大鼠,体质量250±20g.按数字表法将大鼠随机分为4组,每组6只.①对照组(control group,C组):腹腔注射生理盐水10 mL·kg-1;②急性肺损伤(ALI)组:腹腔注射1%内毒素(lipopolysaccharide,LPS) 10 mg*kg-1,30 min后静脉注射油酸(oleic acid,OA)0.15 mL·kg-1;③电刺激(stimulation,ST)组:右颈迷走神经干连接刺激电极,以5 V、2 ms、1 Hz强度持续刺激神经10 min,腹腔注射1% LPS10 mg·kg-1,再持续刺激神经10 min,20 min后静脉注射OA 0.15 mL·kg-1;④他克林(tetrahydroaminoacridine,THA)组:静脉注射胆碱酯酶抑制剂THA 1.5 mg*kg-1,10 min后行急性肺损伤操作.各组动物均于130 min后从颈总动脉采血1 mL行血气分析,处死动物采集标本,分别检测肺组织Toll-样受体-2(Toll-like receptor-2,TLR2)和TLR4 mRNA、核转录因子κB(nuclear factor kappa-B,NF-κB)p65、血清白介素-6(interleukin-6,IL-6)、肺组织髓过氧化物酶(mycloperoxidase,MPO)含量和肺组织湿质量-干质量比(wet weight/dry weight,W/D),HE染色观察左肺组织病理学改变.结果 ALI组与C组比较,pH和动脉氧分压(partial pressure of oxygen,PaO2)均显著下降,二氧化碳分压(partial pressure of carbon dioxide,PaCO2)显著升高;肺泡破坏严重,有大量组织液渗出;肺组织W/D及MPO活性均显著增高;肺组织NF-κB p65蛋白表达明显增强;血清IL-6浓度显著升高;与C组相比,其余3个实验组肺组织TLR2和TLR4 mRNA表达均显著增加,组间比较差异无统计学意义;ST组和THA组与ALI组比较,pH和PaO2均显著升高,PaCO2显著下降;肺组织病理改变明显改善;肺组织W/D及MPO活性均显著降低;肺组织NF-κB p65蛋白表达及血清IL-6浓度显著下降.结论 电刺激迷走神经或者静脉注射他克林可通过激活CAP,减轻LPS复合油酸2次打击致大鼠ALI时的炎性反应;其可能的机制是抑制NF-κB途径活化,在转录前水平发挥抗炎作用,但是不影响ALI时TLR2和TLR4 mRNA的活化.
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