Sufentanil Preconditioning Protects Against Lung Injury Induced By Intestinal Ischemia-reperfusion In Rats And The Role Of Mu, Delta And Kappa Opioid Receptors In It

Objective:To evaluate sufentanil preconditioning on acute lung injury induced by intestinal ischemia and reperfusion induced in rats and the role of delta, kappa, and mu opioid receptors in it.Methods:Forty-eight anesthetized, open-abdomen, male Wistar rats were subjected to45min of occlusion of the superior mesenteric artery and2h of reperfusion except the group Sham. According to the random number seed, the rats were divided into6groups randomly (n=8): group sham operation (S group), intestinal ischemia-reperfusion group (I/R group), sufentanil preconditioning group (SPC group), COTP+SPC group, NTD+SPC group and nor-BNI+SPC group. Rats in the S group were subjected to separate the superior mesenteric artery without being obstructed. Rats in the group I/R were set intestinal ischemia-reperfusion model. In the group SPC rats were administered sufentanil10μg/kg intravenously20min before occlusion. The experiment was repeated with CTOP (a selective μ-opioid receptor antagonist,1mg/kg) or NTD (a selective δ-opioid receptor antagonist.5mg/kg) perfused for a period of10min before SPC respectively while nor-BNI (a selective κ-OR antagonist,5mg/kg) administered15min before. The animals were killed at2h of reperfusion with the intestinal tissue removed to calculate the index of quantitative assessment of intestinal mucous membrane injury. Tissues of left lung were obtained for observation of histopathology with light microscope and the index of quantitative assessment of histologic lung injury was calculated. The apoptosis of pneumocytes was detected using TUNEL and apoptosis index (AI) was calculated. In lung tissues the expression of Bcl-2and Bax protein was detected by immunohistochemical method.Results:Compared with group S, Chiu score, lung injury score, expression of Bax, Bcl-2and apoptosis index increased significantly, whereas Bcl-2/Bax ratio decreased in group IIR (p<0.05). Chiu score, lung injure score, apoptosis index and expression of Bax were lower in group SPC than in group IIR. while expression of Bcl-2and Bcl-2/Bax ratio were higher in group IIR (p<0.01). The protective effects of SPC were attenuated by pretreatment with CTOP and NTD and nor-BNI.Conclusion:Sufentanil preconditioning protects against lung injury induced by intestinal ischemia-reperfusion in rats. Mu, delta and kappa opioid receptors take the roles in it.