To investigate the effect of sevoflurane preconditioning on lung injury induced by limb ischemia-reperfusion in rats and the relationship with endoplasmic reticulum stress.

Forty-five healthy male Sprague-Dawley rats, aged 6-8 weeks, weighing 250-300 g, were randomly allocated into 3 groups(n=15 each)using a random number table: sham operation group(group S), limb ischemia-reperfusion group(group LIR), and sevoflurane preconditioning group(group SP). Limb ischemia-reperfusion was induced by clamping bilateral femoral arteries for 3 h followed by 3 h reperfusion in LIR and SP groups.In group SP, 2.5% sevoflurane was inhaled for 30 min, and 15 min later the model was established.Before ischemia and at 3 h of reperfusion(at the corresponding time point in group S), arterial blood samples were collected for blood gas analysis, and arterial oxygen partial pressure(PaO₂)and arterial carbon dioxide partial pressure(PaCO₂)were recorded.The rats were sacrificed at 3 h of reperfusion, and lung specimens were obtained for determination of wet to dry lung weight ratio(W/D ratio)and total lung water content(TLW)and for microscopic examination of the pathological changes, and index of quantitative evaluation for alveolar damage(IQA)was calculated.The expression of glucose-regulated protein 78(GRP78)and CCAAT/enhancer-binding protein homologous protein(CHOP)protein and mRNA in lung tissues was detected by Western blot and real-time polymerase chain reaction, respectively.

Compared to group S, the PaO₂ was significantly decreased at 3 h of reperfusion, the W/D ratio, TLW and IQA were significantly increased, the expression of GRP78 and CHOP protein and mRNA was significantly up-regulated(P<0.05), and no significant change was found in PaCO₂ in group LIR(P>0.05). Compared to group LIR, the PaO₂ was significantly increased at 3 h of reperfusion, the W/D ratio, TLW and IQA were significantly decreased, the expression of GRP78 and CHOP protein and mRNA was significantly down-regulated(P<0.05), and no significant change was found in PaCO₂ in group SP(P>0.05).

Sevoflurane preconditioning can ameliorate lung injury induced by limb ischemia-reperfusion in the rats, and the mechanism is related to inhibition of endoplasmic reticulum stress.

Anesthetics, inhalation; Ischemic preconditioning; Extremities; Reperfusion injury; Respiratory distress syndrome, adult; Endoplasmic reticulum; Stress