目的 探讨白杨素对脓毒症大鼠肺组织环氧合酶-2(COX-2)和一氧化氮合酶(NOS)表达的影响.方法 将72只健康Wistar大鼠随机分为三组:假手术组、脓毒症急性肺损伤组和白杨素干预组.通过腹腔内注射10mg/kg的脂多糖(LPS)制备脓毒症急性肺损伤大鼠模型.白杨素治疗组大鼠在注射LPS 1h后给予腹腔内注射白杨素20mg/kg,假手术组则注射等量的生理盐水.给予LPS 24h后,水合氯醛麻醉,处死大鼠,检测肺组织湿/干质量比(W/D),应用肺细胞灌洗术方法来进行肺通透指数测定,免疫组织化学方法和Western blot方法检测肺组织COX-2和NOS蛋白的表达.结果 白杨素降低了脓毒症急性肺损伤大鼠的肺水肿及肺血管通透性.LPS诱导后,脓毒症急性肺损伤大鼠肺组织COX-2和NOS蛋白表达的平均光密度值显著升高(P＜0.01);而给于白杨素治疗后,肺组织COX-2和NOS蛋白表达的平均光密度值显著降低(P＜0.01).结论 白杨素减轻脓毒症大鼠的肺损伤可能与抑制COX-2和NOS的表达相关.“,”Objective To investigate the effect of Chrysin on the expression of cyclooxygenase-2 (COX-2) and nitric oxide synthase (NOS) in the lungs of rats with sepsis-associated acute lung injury.Methods 72 healthy Wistar rats were randomly divided into three groups:sham group,acute lung injury group and Chrysin treatment group.A rat model of sepsis induced acute lung injury was prepared by intraperitoneal injection of 10mg/kg lipopolysaccharide(LPS).After the injection of LPS 1H,the rats in the Chrysin treatment group were given intraperitoneal injection of treatment (20mg/kg),and the sham group was injected with the same amount of normal saline.Rats were killed by chloral hydrate anesthesia 24h after administration of LPS,and The lung wet/dry(W/D) weight ratio was detected,the lung permeability index was measured by lung lavage,and The expressions of COX-2 and NOS in lung tissue were detected by immunohistochemistry and Western blot.Results Chrysin reduced the pulmonary edema and pulmonary vascular permeability of rats with sepsis-associated acute lung injury.After LPS induction,the mean optical density of COX-2 and NOS protein in lung tissue of rats with sepsis-associated acute lung injury was significantly increased (P＜0.01);but decreased significantly in Chrysin treatment group than in acute lung injury group (P＜O.01).Conclusion The alleviated acute lung injury by Chrysin might be related to inhibiting the expression of COX-2 and NOS in rats.