谷氨酰胺对大鼠肠缺血/再灌注后肺组织NF-κB表达的影响

The effect of glutamine on NF-κB expression in rat lungs after intestinal ischemia/reperfusion

目的探讨谷氨酰胺预处理对大鼠肠缺血/再灌注后肺损伤的影响及其可能机制。方法SD大鼠25只,随机分为5组:假手术组(Sham),肠缺血/再灌注组(II/R),谷氨酰胺组(Gln),槲皮素组(Q),槲皮素+谷氨酰胺组(Q+G),每组5只。建立大鼠肠缺血/再灌注损伤模型,观察谷氨酰胺预处理以及腹腔注射槲皮素对大鼠肺组织热休克蛋白-70(Heat shock protein-70,HSP-70)表达、核转录因子-κB(Nuclear factor-kappa B,NF-κB)以及肺组织病理变化的影响。结果谷氨酰胺组大鼠肺组织HSP-70的表达较其余各组明显增加(P<0.05);而NF-κB的表达除假手术组外,其他各组均较谷氨酰胺组显著增加(P<0.05);谷氨酰胺组大鼠肺组织髓过氧化物酶(Myeloperoxidase,MPO)以及丙二醛(Malondiadehyde,MDA)含量较其余各组明显降低(P<0.05)。结论谷氨酰胺预处理可抑制大鼠肠缺血/再灌注后肺组织NF-κB的表达,其机制可能与诱导HSP-70表达有关。

Objective To evaluate the effect of pretreatment with glutamine on lung injury induced by intestinal ischemia/reperfusion in rats. Methods Twenty-five adult Sprague Dawley rats weighing 300 - 350 g were randomized into 5 groups： Sham group, Intestinal ischemia/reperfusion group Ⅱ/R）, Glutamine group （Gin）, Quercetin group （Q） and Quercetin ＋ Glutamine group （Q＋ G）. Quercetin or saline was （i. p. ） 4 hours before intestinal ischemia/reperfusion. Glutamine or saline was injected through tail vein 30 min before the occlusion of superior wesenterie artery （SMA）. After 60 min of the occlusion of SMA and 90 min of reperfusion, rats were sacrificed to harvest lung tissues. The levels of heat shock protein 70 （HSP-70） and Nuclear factor-kappa B （NF-κB） in the lung tissues were detected by Western blot. Myeloperoxidase and malondialdehyde and pathological changes were also measured. Results The expression of HSP-70 protein in rat lungs from Gin group was significantly inhanced. The expression of NF-κB in Gin group were obviously lower than other groups （except sham group）. The levels of MPO and MDA in rat lungs was also decreased in Gin group. Conclusions Pretreatment with Glutamine can attenuate lung injury induced by intestinal ischemia/ reperfusion in rats, and the enhancement of HSP-70 expression is possibly one of the potential mechanisms.