Induction of aryl hydrocarbon hydroxylase in primary cultures of type II alveolar lung cells and binding of metabolically activated benzo[a]pyrene to nuclear macromolecules.

Alveolar-like structures cultured on a gelatin sponge substrate are composed of cells resembling type II alveolar pneumonocytes. These cells contain aryl hydrocarbon hydroxylase (AHH) as determined by fluorescent measurements of water-soluble product from the metabolism of polycyclic aromatic hydrocarbons (PAH). Of 3 compounds tested, benzo[a]pyrene (BP) stimulates the highest level of AHH activity. Activity reaches a peak in 6 day cultures and remains relatively stable for a culture period of 12 days. Metabolites of tritium labeled BP interact with nuclear macromolecules in these cells as determined by measurements of 3H binding to DNA, histone and non-histone chromosomal proteins. A preferential binding to the non-histone protein fraction occurs.