title: Metabolism of [3H]arachidonic acid by n-3 polyunsaturated fatty acid-enriched piglet alveolar macrophages.
abstract: The metabolism of [3H]arachidonic acid (3H-AA) by control and omega-3 polyunsaturated fatty acid (n-3 PUFA)-enriched piglet alveolar macrophages (AM) was studied after a 4 and 24 h labeling period. 3H-AA metabolites were separated by gradient HPLC. Incorporation of exogenous 3H-AA for either 4 or 24 h was similar for n-3 PUFA-enriched AM compared with control AM. Calcium ionophore (A23187, 10 microM) stimulated a greater release of 3H-AA from n-3 PUFA-enriched AM compared with control AM. Furthermore, AM labeled for 24 h had a lower spontaneous release and higher stimulated release than those labeled for only 4 h. The major 3H-AA metabolites detected in AM supernatants were PGF2 alpha, LTB4, and 5-HETE. Significant amounts of 3H-PGE2 were observed in the supernatants of those cells labeled for 24 h, but not 4 h. The absence of 3H-TXB2 was notable, since enzyme immunoassay detected significant quantities of this AA metabolite in all of the stimulated cell supernatants. From these data we conclude that n-3 PUFA enrichment of piglet AM alters the metabolism of recently incorporated 3H-AA and that the metabolism of labeled AA may not parallel endogenous AA.
authors.affiliation: Department of Animal Sciences, University of Missouri, Columbia 65211, USA.
authors.forename: K L
authors.initials: KL
authors.lastname: Fritsche
authors.forename: N A
authors.initials: NA
authors.lastname: Cassity
mesh_terms: D000818:Animals; D000833:Animals, Suckling; D016718:Arachidonic Acid / Q000378:metabolism*; D000001:Calcimycin / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D015232:Dinoprostone / Q000378:metabolism; D004281:Docosahexaenoic Acids / Q000378:metabolism; D015118:Eicosapentaenoic Acid / Q000378:metabolism; D015525:Fatty Acids, Omega-3 / Q000494:pharmacology*; D005260:Female; D005527:Food, Fortified; D007476:Ionophores; D007553:Isotope Labeling; D007975:Leukotriene B4 / Q000378:metabolism; D016676:Macrophages, Alveolar / Q000187:drug effects / Q000378:metabolism*; D011247:Pregnancy; D011863:Radioimmunoassay; D013552:Swine / Q000378:metabolism*; D013929:Thromboxane B2 / Q000378:metabolism; D013997:Time Factors; D014316:Tritium
chemical_list: D015525:Fatty Acids, Omega-3; D007476:Ionophores; D014316:Tritium; D007975:Leukotriene B4; D004281:Docosahexaenoic Acids; D016718:Arachidonic Acid; D000001:Calcimycin; D013929:Thromboxane B2; D015118:Eicosapentaenoic Acid; D015232:Dinoprostone; D002118:Calcium