白杨素对脓毒症急性肺损伤大鼠COX-2和NOS表达的影响

Effects of Chrysin on expressions of COX-2 and NOS in rats with sepsis-associated acute lung injury

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)。

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 lOmg/kg lipopolysaccharide（LPS）. After the injection of LPS IH, 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-assoclated acute lung injury was significantly increased （P〈0.01）; but decreased significantly in Chrysin treatment group than in acute lung injury group （P〈0.01）. Conclusion The alleviated acute lung injury by Chrysin might be related to inhibiting the expression of COX-2 and NOS in rats.