仓鼠艰难梭菌相关性腹泻动物模型的建立和评价

Establishment and evaluation of hamster model of Clostridium difficile-associated diarrhea

目的探索建立仓鼠艰难梭菌相关性腹泻动物模型的方法和评价指标。方法以克林霉素皮下注射为诱导(术前1 d),24 h后以临床分离株KH1(10~6~10~8CFU/mL,核糖体型027)或SH9(10~8~10^(10)CFU/mL,核糖体型001)灌胃。观察不同建模方式下仓鼠的全身情况、腹泻和体重变化。至观察终点(第7天或死亡)行结肠组织病理学检查。结果克林霉素100 mg/kg皮下注射,24 h后分别以艰难梭菌KH1或SH9活菌混悬液灌胃后,KH1 10~8CFU/mL剂量组仓鼠全部出现腹泻,至第5天全部死亡;SH9 10^(10)CFU/mL剂量组亦全部发生腹泻,死亡率为66.7%。其他实验组仅1只仓鼠出现腹泻死亡或无腹泻。腹泻仓鼠有稀便及湿尾现象,体重减轻,结肠黏膜充血水肿伴炎性细胞浸润。结论以100 mg/kg克林霉素皮下注射,24 h后10~8~10^(10)CFU/mL艰难梭菌活菌混悬液灌胃,可建立艰难梭菌相关性腹泻模型。

Objective To explore a method for establishing the hamster model of Clostridium difficile-associated diarrhea（CDAD） and the indicators for its evaluation.Methods Clindamycin was administered to hamsters subcutaneously（day 1）.and24 h later infected with C.difficile clinical isolates KH1（ribotype 027,10～6-10～8 CFU/mL） or SH9（ribotype 001,10＊-10＂＇CFU/mL）by gavage.Animals were observed for CDAD symptoms such as diarrhea,weight loss and death.At the end of observation period（day 7 or death）,the cecum was collected from each animal for histological evaluation of inflammation.Results Following a single dose of 100 mg/kg clindamycin subcutaneously,all the animals challenged with KH1（10～8 CFU/mL） developed diarrhea and then died within 5 days.All the hamsters challenged with SH9（10～（10） CFU/mL） developed diarrhea as well but only 66.7%died at the end of observation period.Among other groups,only one or none developed diarrhea and then died.The symptoms of hamsters with diarrhea included loose stool,wet tail and weight loss.On histological examination,congestion,hemorrhage and neutrophil infiltration of the mucosa were observed in the hamsters died of CDAD.Conclusions We have successfully established a hamster CDAD model that allows for future investigations.