Abstract
We investigated pulmonary vascular injury caused by mechanically activated white blood cells (WBCs) . We assessed the pulmonary vascular injury by measuring pulmonary vascular filtration coefficient using the gravimetric method and changes in the pulmonary vascular resistance, in the isolated perfused rat lungs. We activated WBCs by gently shaking in a glass container for 10 sec. After measuring the filtration coefficient under baseline conditions, we added inactive or activated WBCs into the pulmonary artery and then stopped the perfusion for 90 minutes and then reperfused. The filtration coefficient and the perfusate flow in activated WBC group was changed to about 2.5 times and 1/3 as that in the inactive WBC group, respectively. These results indicate the increase in the pulmonary vascular permeability and resistance. We conclude that WBCs which are increased in adhesiveness induce pulmonary vascular injury and increase in pulmonary vascular resistance. These results suggest that WBC activation by mechanical share stress may be partly involved in the pathogenesis of reexpansion pulmonary edema.
