Transformation of arachidonic acid by 5- and 15-lipoxygenase pathways in bovine adrenal fasciculata cells.
[1-14C]Arachidonic acid was incubated with isolated bovine adrenal fasciculata cells for 15 min at 37gC. The metabolites were separated and purified by reverse- and straight-phase high performance liquid chromatography, and identified by gas chromatography-mass spectrometry or radioimmunoassay. Identified metabolites were 5-hydroxy-6,8,11,14-eicosatetraenoic acid (5-HETE), 15-hydroxy-5,8,11,13-eicosatetraenoic acid (15-HETE), leukotriene B4 and 11,14,15-trihydroxy-5,8,12-eicosatrienoic acid (11,14,15-THET). Addition of 15-hydroperoxy-5,8,11,13-eicosatetraenoic acid (15-HPETE), an intermediate metabolite of 15-lipoxygenase pathway to microsomes of bovine adrenal fasciculata cells resulted in the formation of 11,14,15-THET. The formation of 11,14,15-THET by microsomes was not dependent on the presence of NADPH, while it was dose-dependently suppressed by ketoconazole, a potent inhibitor of cytochrome P-450 dependent enzymes. These results indicate that 5- and 15-lipoxygenase pathways of arachidonic acid may exist in bovine adrenal fasciculata cells and that 15-HPETE is further metabolized to 11,14,15-THET by adrenal microsomal cytochrome P-450.
Omura
M
M
Second Department of Internal Medicine, School of Medicine, Chiba University, Japan.
Hirai
A
A
Tamura
Y
Y
Yoshida
S
S
D000818:Animals; D001093:Arachidonate 15-Lipoxygenase / Q000378:metabolism*; D001094:Arachidonate 5-Lipoxygenase / Q000378:metabolism*; D001091:Arachidonate Lipoxygenases / Q000378:metabolism*; D001095:Arachidonic Acids / Q000378:metabolism*; D002417:Cattle; D055598:Chemical Phenomena; D002621:Chemistry; D002851:Chromatography, High Pressure Liquid; D065607:Cytochrome P-450 Enzyme Inhibitors; D066298:In Vitro Techniques; D007654:Ketoconazole / Q000494:pharmacology; D008297:Male; D008861:Microsomes / Q000187:drug effects / Q000201:enzymology; D051381:Rats; D011919:Rats, Inbred Strains; D015383:Zona Fasciculata / Q000166:cytology / Q000187:drug effects / Q000201:enzymology*
D001095:Arachidonic Acids; D065607:Cytochrome P-450 Enzyme Inhibitors; D001091:Arachidonate Lipoxygenases; D001093:Arachidonate 15-Lipoxygenase; D001094:Arachidonate 5-Lipoxygenase; D007654:Ketoconazole