Chronic pulmonary inflammation modulates the fate of proteins administered by the respiratory tract. Organ distribution of radiolabeled proteins.

In a previous report we found that, following intrapulmonary administration of radiolabeled albumin, blood concentrations were higher in rabbits with BCG-induced chronic pulmonary inflammation (CPI) than in normal rabbits. The present study demonstrates that this increased blood concentration was not the result of decreased blood clearance by other organs, indicating that increased absorption through the respiratory tract occurred in the inflamed lungs. In addition, rabbits with BCG-induced CPI had larger hilar lymph nodes and larger concentrations of radioactivity in the hilar lymph nodes, suggesting that the pulmonary lymphatics are a route of increased absorption through inflamed lungs.