Effect of Sho-seiryu-to and Saiboku-to on arachidonic acid metabolism by cultured porcine tracheal smooth muscle cells.

We studied the effect of Sho-seiryu-to and Saiboku-to on arachidonic acid metabolism by cultured porcine tracheal smooth muscle cells. HPLC analysis revealed that both cyclooxygenase derivatives, especially PGE2, and lipoxygenase derivatives released in the culture medium were increased during 24-hour incubation of the tracheal smooth muscle cells with 1, 000μg/ml of Sho-seiryu-to. In contrast, the incubation of the tracheal smooth muscle cells with 1, 000μg/ml of Saiboku-to decreased both cyclooxygenase and lipoxygenase derivatives released in the culture medium. Increased release of PGE2from tracheal smooth muscle cells incubated with Sho-seiryu-to may support the therapeutic benefit for bronchial asthma because of broncho-dilatation effect by PGE2, and the suppression of the production of arachidonic acid metabolites by Saiboku-to may show the antiinflammatory action of Saiboku-to.