Pulmonary tissue produces high amounts of prostaglandins (PGs), leukotrienes (LTs), and hydroxy fatty acids (HFA) in response to a number of stimuli or pathological states. These lipids have diverse biological activity. The goal of this study is two-fold, first to develop an understanding of factors with control biosynthesis of these lipids and second to determine their role in secretory and inflammatory processes of the lung. We have chosen to study the biosynthesis of these lipids in dog tracheal epithelial cells and to determine their role in control of CL- and mucus secretion. Dog trachea cells make primary PGE2 and a number of LTs. LTC4 and 3 unknown LTs are produced. C1- secretion appears to be primarily under control of PGE2 formation but other data suggest a role from LTs. We intend to characterize further the LTs formed and to relate to Cl-1 secretion. We are also examining the formation of LTs in development of asbestosis. Cultures of rat pulmonary macrophages release LTs in response to asbestos exposure. Macrophage releases primarily LTB4 but other unknown LTs are released. We intend to further characterize the products released by asbestos from rat macrophages and to explore the possible relationship between macrophages and the development of asbestosis.