黄芪多糖对环丙沙星体内抗菌后效应的影响

目的:观察黄芪多糖预处理免疫抑制模型小鼠,对环丙沙星体内抗菌后效应(PAE)的影响作用。方法:采用二倍稀释法和菌落计数法,测定环丙沙星体外抗金黄色葡萄球菌标准株ATCC25923的MIC、MBC值。黄芪多糖250 mg.kg-1连续灌胃小鼠1周,灌胃第3天和第6天小鼠分别腹腔注射150 mg.kg-1、100 mg.kg-1环磷酰胺制备免疫抑制模型;采用体外PAE诱导的方法制备含2MIC环丙沙星的菌液感染免疫抑制模型小鼠,观察黄芪多糖对环丙沙星体内PAE的影响,同时进行各组小鼠全血白细胞计数及胸腺与脾脏指数的测定。结果:环丙沙星体外对金黄色葡萄球菌标准株ATCC25923的MIC、MBC分别为0.06~0.12 5μg.mL-1、0.25~1μg.mL-1。模型组小鼠胸腺、脾脏指数及白细胞计数均较空白组显著降低(P0.01),表明免疫抑制模型成功。黄芪多糖与模型组比较,在感染后期对模型小鼠的胸腺、脾脏指数与白细胞计数有一定的改善作用;环丙沙星+黄芪多糖组与环丙沙星组比较,亦对上述指标有一定改善作用。黄芪多糖预处理对环丙沙星的体内PAE无明显延长效应。结论:黄芪多糖对免疫抑制感染模型小鼠的非特异性免疫功能有一定提高作用,但对环丙沙星在模型动物体内的PAE无明显影响。

Effects of Astragalus Polysaccharides on PAE of ciprofloxacin,in vivo

Objective： To observe the effects ofAstmgalus polysaccharide on Post antibiotic effect （PAE） of ciprofloxacin in immunosuppression mice that pretreated by Astragalus polysaccharide. Method： The MIC/MBC value of ciprofloxacin on standard strains of Staphylococcus aureus （ATCC25923） in vitro were measured by using two times dilution method and colony counting method. Mice were orally administrated ofAstragalus polysaccharide 250 mg·kg^-1 for one week, and on third and sixth day mice were given cyclophosphamide 150 mg·kg^-1or 100 mg·kg^-1 to induce immune suppression through intraperitoneal injection. By using the method of inducing PAE in vitro, bacteria liquid which containing 2MIC ciprofloxacin was prepared. Then the model mice were infected by above bacteria liquid, and the effects of Astmgalus polysaccharides on PAE of ciprofloxacin in vivo were observed. And the blood leukocyte count and the thymus/spleen index were measured in mice. Result： The MIC and MBC of ciprofloxacin on ATCC25923 were 0.06 μg·mL^-1～0.125μg·mL^-1 and 0.25μg·mL^-1 ～ 1μg·mL^-1 respectively in vitro. Compared with control group, the spleen and thymus index and white blood cell counting of model group were significantly decreased （P〈0.01）, which indicated that the model in mice was successful. In the later stage of infection, compared with the model group, Astragalus polysaccharide could improve the thymus/spleen index and white blood cell counting in mice. Compared the ciprofloxacin group with （ciprofloxacin ＋ astragalus polysaccharides） group, the later group also showed the improving effects on organ index and white blood cell counting. But no significant difference on PAE of ciprofloxacin was observed by pretreatment with Astragalus polysaccharide in vivo.