大黄对家兔内毒素性急性肺损伤的保护作用研究

目的:观察大黄对家兔内毒素性急性肺损伤(ALI)的保护作用。方法:12只雄性新西兰兔待氧合指数(PaO2/FiO2)≤300mmHg(1mmHg=0.133kPa)时,将动物随机分为两组,每组6只。生理盐水对照组注入等量生理盐水;大黄组胃内注入大黄20g/kg。观察基础值,ALI时以及ALI后1、2、3、4、5和6h各时间点两组胃肠黏膜内pH值(pHi)、PaO2/FiO2、肺动态顺应性(Cdyn),测定ALI的生物学指标超氧化物歧化酶(SOD)活性,以及支气管肺泡灌洗液(BALF)中蛋白的含量。实验结束后,开胸取肺行组织学检查。结果:生理盐水对照组pHi在ALI后4、5和6h均较基础值时降低(P均<0.05),在ALI后5h和6h较ALI时降低(P均<0.05);大黄组pHi在ALI后4h和5h较生理盐水对照组升高(P均<0.05),而在6h较生理盐水对照组同时间点显著升高(P<0.01)。两组PaO2/FiO2在ALI后均有不同程度下降,且两组PaO2/FiO2在ALI后5h和6h差异有显著性(P<0.05和P<0.01)。两组Cdyn在ALI后均有不同程度的下降,但大黄组下降幅度较小,且两组Cdyn在ALI后5h和6h差异有显著性(P均<0.05)。两组SOD活性大黄组显著高于生理盐水对照组(P<0.01)。大黄组BALF中蛋白含量低于生理盐水对照组(P<0.05)。肺组织切片显示大黄组肺组织损伤明显较生理盐水对照组轻。结论:胃内注入大黄对兔内毒素性ALI有保护作用。

Protective effect of rhubarb on lipopolysaccharide induced acute lung injury in rabbits

Objective: To observe the protective effect of rhubarb on lipopolysaccharide induced acute lung injury(ALI) in rabbits. Methods: Twelve male New Zealand rabbits were randomly divided into rhubarb group and control group(n=6 in each group) when partial pressure of oxygen in artery(PaO_2)/fractional concentration of inspired oxygen (FiO_2) reduced below 300 mm Hg(1 mm Hg=0.133 kPa). In the control group, rabbits received normal saline (NS) through stomach tube in equal volnme as that given in the rhubarb group, and in rhubarb group, rabbits received rhubarb infusion of 20 g/kg. The gastric intramucosal pH(pHi), PaO_2/FiO_2 and lung dynamic compliance(Cdyn) were observed at basic line, onset of ALI and 1, 2, 3, 4, 5 and 6 hours after ALI. Biological markers of ALI such as superoxide dismutase (SOD) and protein content in the bronchoalveolar lavage fluid (BALF) were measured. Histopathological examinations of lung were performed at the end of experiment. Results: In NS control group, at 4, 5 and 6 hours after ALI, pHi was lower than that at base values(all P<0.05), and at 5 and 6 hours after ALI, pHi was lower than that at onset of ALI(all P<0.05). In rhubarb group, at 4 and 5 hours after ALI, pHi was higher than that in NS control group(both P<0.05); at 6 hours after ALI, pHi was significantly higher than that at the same time point in NS control group (P<0.01). PaO_2/FiO_2 was reduced to a certain degree in both groups after ALI, and it was higher in rhubarb group than that in NS control group at 5 and 6 hours after ALI(P<0.05 or P<0.01). Cdyn was decreased significantly after ALI in the two groups, and it was higher in rhubarb group than that in NS control group at 5 and 6 hours after ALI (both P<0.05).The activity of SOD in rhubarb group was greater compared with that in NS control group (P<0.01). The protein content in the BALF in rhubarb group was lower than that in the NS control group (P<0.05).The histopathological change of lung injury in rhubarb group were significantly milder than that in NS control group. Conclusion: Infusing rhubarb 20 g/kg into stomach has protective effect on ALI induced by lipopolysaccharide.