复方甘草酸单铵可溶性粉对恩诺沙星联合LPS致鸡肝损伤保护机制研究

Protective effects of compound ammonium glycyrrhizin soluble powder on liver injury induced by LPS and enrofloxacin in chickens

104羽海蓝蛋鸡随机分为空白组(Ⅰ)、模型组(Ⅱ)、复方甘草酸单铵可溶性粉(CAG)预防组(Ⅲ)、CAG治疗高剂量组(Ⅳ)和CAG治疗低剂量组(Ⅴ),除Ⅰ组外,各组连续灌服恩诺沙星100 mg.kg-1,1次.d-1,第3天灌药同时腹腔注射脂多糖粗提液(LPS)4 mL.kg-1以建模。Ⅲ组在灌服恩诺沙星前3 d混合饮用CAG 40 mg.L-1至建模止;Ⅳ、Ⅴ组腹腔注射LPS同时分别灌服22.5和7.5 mg.kg-1CAG,2次.d-1,重复3 d。各组均在腹腔注射LPS后分别于6、24和48 h采血,检测血清生化指标,观察肝组织病理学变化。试验结果如下:Ⅱ组鸡血清ALT、AST、γ-GT、TBIL、MDA和NO水平在6、24和48 h均显著高于Ⅰ组,而TP、ALB、SOD和GSH均显著低于Ⅰ组。与Ⅱ组相比,Ⅲ组各指标多在6和24 h差异显著,只MDA、ALB和GSH持续至48 h仍显著,Ⅳ组各指标均在24和48 h差异显著,Ⅴ组各指标差异均不显著。仅Ⅳ组DBIL浓度在24和48 h较Ⅰ组显著升高,其余组无显著差异;Ⅳ组较其他组鸡肝细胞病变改善最大。结论:在自由基损伤介导肝损伤过程中,CAG有一定保护作用,效果受给药时机和剂量影响。

A total of 104 chickens was divided randomly into 5 groups：Group I served as normal control. Group Ⅱ , Ⅲ, IV, and V were administered enrofloxacin（ 100 mg·kg^-1） once a day, and on the 3rd day, administered lipopolysaceharide crude extract（LPS） （4 mL· kg^-1 ） at the same time. Group Ⅱ was maintained as liver injury control. Group Ill received preventive treatment of compound ammonium glycyrrhizin soluble powder（CAG） in drinking water at the dose of 40 mg·L^-1（ by ammonium glycyrrhizin, the same as follows） for three days before enrofloxaein treatment, and till to LPS treatment. Group IV and V received CAG at the dose of 22.5 and 7.5 mg·kg^-1, twice a day for three days after LPS treatment. Eight chickens were sacrificed at 6,24,48 h post-treatment with LPS and their blood sample were harvested for detection of serum biochemical indexes. Their livers were dissected out and evaluated for histopathological changes. Result ： at 6,24,48 h post-treatment with LPS, the levels of serum ALT, AST, γ-GT, TBIL, MDA and NO were significantly higher, and TP, ALB, SOD and GSH were significantly lower in Group II than in Group I . Compared to Group Ⅱ , in Group m ,there was significant improvment of most indicators at 6 h and 24 h,but MDA,ALB and GSH at 6,24 and 48 h;in group IV, there was significantly improvment of all indicators at 24 h and 48 h. There was no obvious alteration were still significantly higher in Group V. There was significantly higher improvement in DBIL at 24 h and 48 h in Group IV than in Group I , no obvious alteration in others. The results of pathological study also support the results of biochemical findings. Conclusion ： the liver injury effect might be related to oxygen free radicals. CAG treatment could reduce such liver injury, probably by its antioxidant property.