Epithelium-derived linoleic acid metabolites modulate airway smooth muscle function.

Cultured epithelial cells obtained from guinea pig tracheal preparations metabolized arachidonic acid into 5- and 15-hydroxy-eicosatetraenoic acid and into the prostaglandins E2 and F2 alpha. Linoleic acid was converted by the epithelial cells into 9-hydroxy-octadecadienoic acid (9-HODE) and smaller amounts of 13-HODE. It was further investigated whether linoleic acid metabolites are of importance for the regulation of airway smooth muscle function. 13-HODE caused an increase of maximal contraction of tracheal rings to histamine, while 9-HODE had no effect.