title: Cigarette smoke exposure alters [14C]arachidonic acid metabolism in aortas and platelets of rats fed various levels of selenium and vitamin E.
abstract: Rats were placed on a basal diet supplemented with 0, 0.03, or 3 ppm selenium and 0 or 20 ppm vitamin E for 41-43 wk. Selenium deficiency decreased hepatic glutathione peroxidase activity and lowered both aortic prostacyclin (PGI2) and platelet thromboxane (TXA2) production compared to selenium- and vitamin E-supplemented animals. Vitamin E deficiency increased hepatic lipid peroxidation and decreased aortic PGI2 synthesis. Rats exposed daily for 31-32 wk to fresh smoke from a UK 2R1 reference cigarette had carboxyhemoglobin levels of 0.75 +/- 0.12 and 4.73 +/- 0.12% in sham- and smoke-exposed groups, respectively. Animals chronically exposed to cigarette smoke displayed a nearly twofold increase in pulmonary arylhydrocarbon hydroxylase activity. Smoke exposure produced a 26-33% decrease in aortic PGI2 synthesis compared to shams in the Se3E20, Se0.03E20, and Se3E0 groups. Smoking also increased platelet thromboxane 91% and 98% in the Se3E20 and Se3E0 groups compared to shams. It is concluded that cigarette-smoke exposure and selenium or vitamin E deficiency alter aortic PGI2 and platelet TXA2 production.
mesh_terms: D015121:6-Ketoprostaglandin F1 alpha / Q000096:biosynthesis; D000818:Animals; D001011:Aorta / Q000378:metabolism*; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000378:metabolism*; D001792:Blood Platelets / Q000378:metabolism*; D002250:Carbon Radioisotopes; D005979:Glutathione Peroxidase / Q000032:analysis; D066298:In Vitro Techniques; D008099:Liver / Q000201:enzymology; D008297:Male; D010947:Plants, Toxic; D051381:Rats; D011916:Rats, Inbred F344; D012643:Selenium / Q000494:pharmacology*; D012906:Smoke / Q000009:adverse effects*; D013929:Thromboxane B2 / Q000096:biosynthesis; D014026:Nicotiana; D014810:Vitamin E / Q000494:pharmacology*
chemical_list: D001095:Arachidonic Acids; D002250:Carbon Radioisotopes; D012906:Smoke; D014810:Vitamin E; D016718:Arachidonic Acid; D013929:Thromboxane B2; D015121:6-Ketoprostaglandin F1 alpha; D005979:Glutathione Peroxidase; D012643:Selenium