Effect of lidocaine on lung injury and the expression changes of NF-κB by large tidal volume ventilation in rat lung

[Objective] To observe the effects of lidocaine on lung injury and the expression changes of NF-κB by large tidal volume mechanical ventilation on rat lung.[Methods] 36 depuratory-class adult male SD rats were randomly divided into three groups: R group、N group and L group.The tidal volume of N group or L group wes 40 ml/kg;The experiment was terminated atlasted for 3 hours.Respirating air.The animals' BP,HR,ECG and PET CO_2 were monitored,blood gas analysis was detected terminating the experiment.The endotoxin contents in the blood were checked before mechanical ventilation,the rats detected ofwith endotoxin contents were knocked out the experiment to guarantee the experiment would not be influenced by endotoxin.Aseptic techniques were strictly executed throughout the whole experiment.6 rats in each group were injected by EB.Pathomorphological integration and the expression of NFκB mRNA expression in whole lung homogenates was assessed by RT-PCR,the expression of NF-κB protein on were assessed.[Results] There was no significant pathomorphological changes in R group.Compared with R group,lung pathomorphological integrationchanges were more significant,W/D and the content of EB were all elevated(P0.05 or P0.01) in N group and L group;WBC in L group had no change and elevated significantly in N group(P0.01).The expression of NF-κB protein and NF-κB mRNA in lung were significantly higher in N group than in R group(P0.01),but the difference between L group and R group was not significant(P0.05).[Conclusions] The large tidal volume mechanical ventilation on rat lung increased the lungs' permeability and inflammatory response,induced up-regulation of NF-κB expression in rat's lung.Lidocaine inhibited this inflammatory response and up-regulation of NF-κB expression.