[Animal modeling] Establishment of cough variant asthma model in Brown Norway rats

  Objective: To establish a simple and practical animal model of cough variant asthma in Brown's Norway (BN) rats sensitized with ovalbumin (OVA).

  Methods: Thirty six BN rats were divided into three groups: normal control group, model control group and administration group. On the first day, rats were intraperitoneally injected with 2mg egg protein and 100mg Al (OH) 3 gel, and then intraperitoneally injected with 0 01mgOVA and 100mgAl (OH) 3 gel, rats in the normal control group were intraperitoneally injected with the same amount of normal saline. Three weeks later, the model control group and the drug administration group were atomized with 1% OVA, and the normal control group was atomized with normal saline once every other day, a total of 7 times. On the day of atomization, the administration group began to give medicine by gavage, and the other two groups were given the same amount of normal saline once a day, 14 times in total. 24 hours after the last administration, the cough induced by capsaicin and pulmonary function test (stimulation test) were conducted.

  Results: Compared with the normal control group, the number of coughs in the model control group increased significantly (P<0.01), the total inspiratory airway resistance (RL) increased significantly (P<0.05), and the dynamic compliance (Cdyn) decreased significantly (P<0.05); Compared with the model control group, the number of coughs in the drug administration group was significantly reduced (P<0.05), RL was significantly decreased (P<0.05), and Cdyn was significantly increased (P<0.05).

  Conclusion: This animal model is similar to cough variant asthma in many clinical features, and is easy to operate, so it can be used as an animal model of cough variant asthma.