title: Effects of nicotine on cardiac prostaglandin and platelet thromboxane synthesis.
abstract: 1 Rabbit hearts were perfused with a solution containing [14C]-arachidonic acid (AA) and various concentrations of nicotine (3 x 10(-8) to 3 x 10(-5) M). The venous effluent was collected and extracted for lipid acid material, which was subsequently subjected to thin layer radiochromatography. 2 Human platelets were incubated with nicotine (10(-8) to 10(-4) M), in the absence or presence of unlabelled AA. The amount of smooth muscle stimulating activity resulting from 30s of incubation was tested on a rabbit aortic strip. 3 In hearts perfused with [14C]-AA; nicotine induced a dose-related depression of the release of [14C]-6-keto-prostaglandin F1alpha, and a parallel increase of [14C]-prostaglandin E2. 4 Nicotine neither induced synthesis of thromboxane in human platelets, nor affected the platelet synthesis of thromboxane induced by AA. 5 It is suggested that nicotine affects the metabolism of prostaglandin endoperoxides in the heart by inhibiting their conversion to prostacyclin and facilitating, directly or indirectly, the formation of prostaglandin E2.
mesh_terms: D000818:Animals; D001095:Arachidonic Acids / Q000494:pharmacology; D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism*; D066298:In Vitro Techniques; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009206:Myocardium / Q000378:metabolism*; D009538:Nicotine / Q000494:pharmacology*; D011453:Prostaglandins / Q000096:biosynthesis*; D011817:Rabbits; D013931:Thromboxanes / Q000096:biosynthesis*
chemical_list: D001095:Arachidonic Acids; D011453:Prostaglandins; D013931:Thromboxanes; D009538:Nicotine