In vivo observation of leukocyte adherence in asthmatic rats

Inflammation of the airway is thought to be one of the main factors contributing to the bronchial hyperresponsiveness which is characteristic for allergic asthma. Leukocyte adhered to vascular endothelium, which is caused by the interaction of adhesion molecules, is necessary for inflammatory cells infiltration. To elucidate the mechanism of leukocyte infiltration in asthma, we developed an animal model of asthma by using Wistar rats. In this model the leukocyte adhered to tracheal venular endothelium was assessed by in vivo microscopic observation. The results showed that the number of leukocytes adhered to tracheal venular endothelium increased significantly in asthmatic rats, as compared with those of controls, and it was accompanied by a significant inflammatory cell infiltration in lung tissue. It is concluded that the increase of leukocyte adhered to venular endothelium is pivotal in inflammatory cell infiltration in asthmatic rats. Copyright (C) 1996 Elsevier Science Ltd