Metabolism of Environmental Pollutants by the Isolated Perfused Lung

An isolated perfused rabbit lung system was developed for the study of pulmonary metabolism of foreign compounds. The main features of the system include the use of autologous whole blood, constant pressure perfusion, subatmospheric ventilation, and measurement of a variety of physiological and biochemical parameters. Pulmonary metabolism of benzo(a)pyrene has been investigated with this system. In addition to the 3-hydroxy metabolite, three dihydrodiols and an unidentified polar metabolite were also found. The polar metabolite accounted for approximately 50% of all metabolites found in the five compartments of the perfusion system. Pretreatment with 3-methylcholanthrene increased total metabolism of benzo(a)pyrene and shifted the pattern of metabolites. The perfusion system for the rabbit has been extensively modified for use with rats and guinea pigs. These smaller animals are currently being used to investigate pulmonary metabolism of trichloroethylene.