ABSTRACT
Objective To compare the different methods of administration of diacetyl (DA)-established bronchiolitis obliterans (BO)murine model so as to establish a simple,easy-to-operate and stable BO murine model. Methods SPF grade C57BL/6 male mice (6 to 8 weeks)were randomly divided into four groups with 10 mice in each group:oropharyngeal aspiration group (OPR),intratracheal instillation group (ITI),and control groups (OPR-CON and ITI-CON).OPR group was treated with DA (400 mg/kg,327 mg/kg)by oropharyngeal aspiration;ITI group received DA (400 mg/kg,327 mg/mL)through intratracheal instillation;OPR-CON group and ITI-CON group were treated with sterilized distilled water instead of DA,while the other experimental conditions were the same as those in OPR and ITI groups.The mice were kept in SPF-class animal center for 7 d to collect specimens. Collected bronchoalveolar lavage fluid (BALF)and the left lung were examined pathologically.Results Male C57 BL/6 mice were treated with a single dose of DA (400 mg/kg,327 mg/kg)by OPR or ITI,which could establish BO model.The successful model was evaluated by pulmonary function,BALF counts and pathological examination. Airway hyperresponsiveness occurred with the two-method resulted BO.And two methods of instilling DA resulted in airway injury,lumen occlusion,infiltration of inflammatory cells in the airway and around the vessels.The mortality rate of mice was up to 60% and the success of model construction was only 20% in BO model by oropharyngeal aspiration of DA,while that in ITI group mortality was only 30%,the success of model construction was up to 60%.There was no death in control groups.Conclusion BO murine model could be successfully established by OPR or ITI of DA (400 mg/kg,327 mg/mL).However,the BO model was established well by ITI of DA with lower mortality rate.Therefore,ITI of DA-established BO murine model is recommended for use.