Effects of Nicotine on the Generation of Lipoxygenase Products

Summary

The effects of nicotine on human polymorphonuclear granulocytes (PMN) and platelets were studied with regard to the generation of lipoxygenase-derived arachidonic acid metabolites. The treatment of PMN with nicotine-tartrate leads to a concentration-dependent decrease of leukotriene B4 generation induced by Ca-ionophore A23187. In contrast, with opsonized zymosan as leukotriene inducing stimulus the same concentration of nicotine-tratrate significantly increased leukotriene B4 generation. Only nicotine-tratrate concentrations higher than 1×10⁻⁵ M showed these modulatory effects. High concentrations of nicotine-tratrate increased the metabolism of LTB4 to its omega-oxidated products; the intermediate products of omega-oxidation, the 20-OH-LTB4, was significantly enhanced, whereas the amount of 20-COOH-LTB4, was decreased. The results obtained by incubation of human platelets with nicotine-tratrate demonstrate no effect in platelet aggregation, the metabolism of platelet activating factor (PAF) and release of serotonin. Only high concentrations of nicotine tratrate decreased the generation of 12-HETE.