Ethanol-enhanced transmembrane penetration of arachidonic acid and activation of the 5-lipoxygenase pathway in human leukocytes.

Enhanced penetration by ethanol of exogenous arachidonic acid into human leukocyte preparations results in the production of large amounts of eicosanoids including 5-, 12- and 15-hydroxyeicosatetraenoic acids as well as the leukotrienes C4 delta 6-trans-leukotriene B4, 12-epi-delta 6-trans-leukotriene B4, leukotriene B4 and 5(S), 12(S)-dihydroxyeicosatetraenoic acid. The production of these compounds is affected by the concentrations of both ethanol and arachidonic acid independently in a complex manner with stimulation at lower concentrations and later relative inhibition. It was shown that the resulting leukotriene B4 exhibited the same specific activity as exogenous arachidonic acid when labelled substrate was used.