[Role of p38 mitogen activated protein kinase signaling pathway in lung ischemia-reperfusion protection offered by HOE642].

Objective: To explore the protective effect of sodium channels antagonists HOE642 on lung ischemia reperfusion and the role of the p38 mitogen activated protein kinase (p38MAPK) signaling pathway in this process.
 Methods: A total of 36 mice were randomly divided into a sham operation group (SHAM group), a lung ischemia reperfusion group (I/R group) and a lung ischemia reperfusion+HOE642 group (HOE group). The water content was detected by electronic scales, and the lung tissue pathological changes were observed under optical microscope. The inflammatory cytokines including IL-6 and TNF-α were examined by ELISA. The intracellular calcium fluorescence intensity was examined and observed under fluorescence microscope, and the protein expression of p38MAPK was detected by Western blot.
 Results: Lung water content in the HOE group was lower than that in the I/R group, but higher than that in the SHAM group (both P<0.05). Lung interstitial edema, hemorrhage, lung tissue inflammatory cells infiltration were significantly alleviated in the HOE group than those in the I/R group, while the injury in the HOE group was aggravated than those in the SHAM group (both P<0.05). The IL-6 and TNF-α in lung tissues in the HOE group were lower than those in the I/R group, but higher than those in the SHAM group (both P<0.05). Intracellular calcium fluorescence intensity in the HOE group was lower than that in the I/R group, but higher than that in the SHAM group (both P<0.05). The protein expression of p38MAPK in lung tissues in the HOE group was lower than that in the I/R group, but higher than that in the SHAM group (both P<0.05).
 Conclusion: HOE642 may exert protective effect on pulmonary I/R injury through regulation of the p38MAPK signaling pathway, resulting in reduction of intracellular calcium ion concentration and calcium overload, and decrease of inflammatory response.