右美托咪定对单肺通气大鼠非通气侧肺组织细胞焦亡的影响

Effect of dexmedetomidine on pyrolysis of lung tissue on non-ventilated side of rats with one-lung ventilation

目的观察右美托咪定对单肺通气大鼠非通气侧肺组织细胞焦亡的影响。方法24只雄性SD大鼠采用随机数字表法分为模型组、双肺通气组及右美托咪定组,每组8只。双肺通气组行双肺通气,模型组及右美托咪定组行单肺通气。同时模型组及双肺通气组予0.9%氯化钠注射液4 ml静脉注射,右美托咪定组术前10 min予右美托咪定5μg/kg静脉输注后,以2.5μg/(kg·h)的速率输注至通气结束。比较3组大鼠机械通气前(T0)、机械通气后30 min(T1)、机械通气结束即刻(T2)、呼吸指数(RI)、氧合指数(OI)。处死各组大鼠后比较各组大鼠肺湿干重比(W/D)及肺含水率,采用酶联免疫吸附试验(ELISA)法测定肿瘤坏死因子-α(TNF-α)、白细胞介素(IL)-6、IL-1β、IL-10含量。实时定量聚合酶链反应(Real-time PCR)检测肺组织Nod样受体家族包含pyrin结构域蛋白3(NLRP3)、半胱氨酰天冬氨酸特异性蛋白酶(Caspase)-1 mRNA的表达,组间两两比较采用LSD-t检验。结果模型组T1、T2时间点大鼠OI(T1:224.97±13.47、T2:274.24±31.68)均低于双肺通气组(T1:349.77±44.32、T2:404.26±30.56)、RI(T1:5.30±0.23、T2:8.61±0.61)均高于双肺通气组(T1:2.15±0.33、T2:5.45±0.04);而右美托咪定组T1、T2时间点OI(T1:284.02±34.86、T2:320.54±44.45)均高于模型组(T1:224.97±13.47、T2:274.24±31.68)、RI(T1:4.02±0.15、T2:6.95±0.28)均低于模型组(T1:5.30±0.23、T2:8.61±0.61),差异均有统计学意义(F=27.831、26.632、330.620、133.311,P<0.05)。模型组大鼠肺W/D、总肺含水量(TLW)[(5.46±0.49)%、(3.89±0.68)%]均高于双肺通气组[(2.95±0.52)%、(2.28±0.29)%],而右美托咪定组W/D、TLW[(4.45±0.19)%、(3.61±0.28)%]均低于模型组[(5.46±0.49)%、(3.89±0.68)%],差异均有统计学意义(F=71.202、28.141,P<0.05)。模型组肺组织大鼠TNF-α、IL-6、IL-1β水平[(218.13±37.40)pg/g、(191.34±25.66)pg/g、(388.54±68.04)pg/mg]均高于双肺通气组[(101.26±12.53)pg/g、(120.44±11.08)pg/g、(110.45±29.34)pg/mg],IL-10水平[(98.13±7.38)pg/g]低于双肺通气组[(180.22±16.61)pg/g];而右美托咪定组大鼠肺组织TNF-α、IL-6、IL-1β水平[(126.64±32.20)pg/g、(152.57±16.30)pg/g、(244.36±28.97)pg/mg]均低于模型组[(218.13±37.40)pg/g、(191.34±25.66)pg/g、(388.54±68.04)pg/mg],IL-10水平[(128.12±23.53)pg/g]均高于模型组[(98.13±7.38)pg/g],差异均有统计学意义(F=34.980、28.891、73.338、46.853,P<0.05)。模型组肺组织大鼠NLRP3、Caspase-1 mRNA表达(7.91±1.50、8.78±0.65)均高于双肺通气组(4.92±0.87、7.70±0.33),而右美托咪定组大鼠肺组织NLRP3、Caspase-1 mRNA表达(6.13±1.05、8.73±1.61)均低于模型组(7.91±1.50、8.78±0.65),差异均有统计学意义(F=13.151、3.912,P<0.05)。结论右美托咪定能够通过抑制NLRP3/Caspase-1通路介导的细胞焦亡保护单肺通气大鼠非通气侧肺组织。

Objective To observe the effect of dexmedetomidine on the pyrolysis of lung tissue on the non-ventilated side of one-lung ventilation rats.Methods Totally,24 male SD rats were divided into 3 groups:model group,double-lung ventilation group and dexmedetomidine group,with 8 rats in each group.The two-lung ventilation was performed on the two-lung ventilation group,and single-lung ventilation was performed on the model group and the dexmedetomidine group.At the same time,the model group and the two-lung ventilation group were given 0.9%sodium chloride injection 4 ml intravenously,and the dexmedetomidine group was given dexmedetomidine 5μg/kg intravenously 10 min before the operation,followed by 2.5μg/(kg·h)rate of infusion to the end of ventilation.The respiratory index(RI)and oxygenation index(OI)were compared among the three groups before mechanical ventilation(T0),30 min after mechanical ventilation(T1),immediately after stopping mechanical ventilation(T2).After the animals were sacrificed,the lung wet-to-dry weight ratio(W/D)and lung water content were compared,and the contents of tumor necrosis factor-α(TNF-α),interleukin(IL)-6,IL-1β,and IL-10 were determined by enzyme linked immunosorbent assay(ELISA).Real-time quantitative polymerase chain reaction(Real-time PCR)was used to detect the expression of NLR family pyrin domain containing 3(NLRP3)and cysteinyl aspartate-specific protease(Caspase)-1 mRNA in lung tissue.Results The OI at T1 and T2 was lower in the model group(T1:224.97±13.47,T2:274.24±31.68)than in the double-lung ventilation group(T1:349.77±44.32,T2:404.26±30.56),and the RI in the model group(T1:5.30±0.23,T2:8.61±0.61)was higher than that in the double-lung ventilation group(T1:2.15±0.33,T2:5.45±0.04).The OI at T1 and T2 was higher in the dexmedetomidine group(T1:284.02±34.86,T2:320.54±44.45)than in the model group(T1:224.97±13.47,T2:274.24±31.68),and the RI in the dexmedetomidine group(T1:4.02±0.15,T2:6.95±0.28)was lower than that in the model group(T1:5.30±0.23,T2:8.61±0.61),and the difference was statistically significant(F=27.831,26.632,330.620,133.311,P<0.05).The lung W/D and total lung water content(TLW)in the model group[(5.46±0.49)%,(3.89±0.68)%]were higher than in the double-lung ventilation group[(2.95±0.52)%,(2.28±0.29)%],and the W/D and TLW in the dexmedetomidine group[(4.45±0.19)%,(3.61±0.28)%]were lower than in the model group[(5.46±0.49)%,(3.89±0.68)%],and the differences were statistically significant(F=71.202,28.141,P<0.05).The levels of TNF-α,IL-6 and IL-1βin the model group[(218.13±37.40)pg/g,(191.34±25.66)pg/g,(388.54±68.04)pg/mg]were higher than those in the double-lung ventilation group[(101.26±12.53)pg/g,(120.44±11.08)pg/g,(110.45±29.34)pg/mg],and the level of IL-10 in the model group[(98.13±7.38)pg/g]was lower than that in the double-lung ventilation group[(180.22±16.61)pg/g];the levels of TNF-α,IL-6 and IL-1βin the dexmedetomidine group[(126.64±32.20)pg/g,(152.57±16.30)pg/g,(244.36±28.97)pg/mg]were lower than those in the model group[(218.13±37.40)pg/g,(191.34±25.66)pg/g,(388.54±68.04)pg/mg],and the levels of IL-10[(128.12±23.53)pg/g]were higher than those in the model group[(98.13±7.38)pg/g],and the differences were statistically significant(F=34.980,28.891,3.338,46.853,P<0.05).The mRNA expression levels of NLRP3 and Caspase-1 in the model group(7.91±1.50,8.78±0.65)were higher than those in the double-lung ventilation group(4.92±0.87,7.70±0.33),and those in the dexmedetomidine group(6.13±1.05,8.73±1.61)were lower than those in the model group(7.91±1.50,8.78±0.65),and the differences were statistically significant(F=13.151,3.912,P<0.05).Conclusion Dexmedetomidine can protect the non-ventilated lung tissue of one-lung ventilation rats by inhibiting the pyrolysis mediated via the NLRP3/Caspase-1 pathway.