Continuous intravenous infusion of lidocaine on acute lung injury and inflammatory response in septic rats

Abstract

Objective To investigate the effect of lidocaine on lung injury and expression of inflammatory factors in septic rats. Methods Sixty male adult Sprague Dawley rats were randomly divided into the sham operation group, cecal ligation and puncture (CLP) group, ulinastatin group and lidocaine group, with 15 rats in each group. The abdominal cavity of rats was opened and sutured in the sham operation group, and sepsis models in the other groups were established by the CLP method. Rats in the lidocaine group were continuously pumped with lidocaine through the tail vein at a dose of 10 mg·kg-1·h-1 for 3 h after injecting a loading dose of 10 mg/kg. Rats in the ulinastatin group were given CLP and continuously pumped with ulinastatin through the tail vein at a dose of 100 000 U·kg-1·h-1 for 3 h. Rats in the sham operation and CLP groups were injected with equal amount of isoosmotic NaCl solution. The levels of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and high mobility group box 1 (HMGB1) in serum were determined by enzyme-linked immunosorbent assay (ELISA), as all rats were sacrificed at 24 h after CLP. The expression of HMGB1 mRNA in lung tissue was detected by real-time fluorescence quantitative PCR, and the pathological changes of lung tissue in each group were observed by hematoxylin-eosin (HE) staining. Another 40 rats (10 in each group) were used to observe the death condition at 72 h in 4 groups. Results The levels of TNF-α, IL-6, HMGB1, and HMGB1 mRNA in serum of the four groups were significantly different (F=189.886, 237.952, 175.999, 179.491; all P 0.008). Conclusions By reducing the expressions of TNF-α, IL-6 and HMGB1 and inhibiting the HMGB1 mRNA expression in lung tissue, continuous intravenous injection of lidocaine can alleviate pulmonary injury induced by sepsis and effectively improve the survival rate. The effect of lidocaine on inflammatory reaction and lung protection after sepsis is similar to that of ulinastatin. Key words: Lidocaine; Ulinastatin; Sepsis; Acute lung injury; High mobility group box 1