High-performance liquid chromatography-thermospray mass spectrometry of epoxy polyunsaturated fatty acids and epoxyhydroxy polyunsaturated fatty acids from an incubation mixture of rat tissue homogenate.
A method for the analysis of epoxy polyunsaturated fatty acids (EpPUFAs) and epoxyhydroxy polyunsaturated fatty acids (EpHPUFAs) in rat tissue homogenate, with homo-gamma-linolenic acid (20:3, n - 6), arachidonic acid (20:4, n - 6), eicosapentaenoic acid (20:5, n - 3) or docosahexaenoic acid (22:6, n - 3) as a substrate, has been developed. Extraction with dichloromethane at pH 4-5 and concentration in the presence of pyridine were performed. Spectral analysis of chromatograms obtained with high-performance liquid chromatography-thermospray mass spectrometry showed the presence of EpPUFAs, EpHPUFAs and dihydroxy metabolites (DiHPUFAs) of EpPUFAs corresponding to each precursor fatty acid. On a selected-ion monitoring chromatogram, many EpPUFAs, EpHPUFAs and DiHPUFAs in an extract from an incubation mixture of each precursor fatty acid in aged rat tissue homogenate were detected simultaneously within 70 min. EpPUFAs and DiHPUFAs derived from 20:3 (n - 6) or 20:5 (n - 3) were detected in significant amounts. From these results, a highly active cytochrome P450 system or non-enzymic oxidative reactions in aged rat tissue homogenate were suggested.
Yamane
M
M
Department of Biochemistry, Tokyo Medical College, Japan.
Abe
A
A
Yamane
S
S
D000818:Animals; D016718:Arachidonic Acid / Q000032:analysis / Q000378:metabolism; D001923:Brain Chemistry; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D004281:Docosahexaenoic Acids / Q000032:analysis / Q000378:metabolism; D015118:Eicosapentaenoic Acid / Q000032:analysis / Q000378:metabolism; D004852:Epoxy Compounds / Q000032:analysis*; D005231:Fatty Acids, Unsaturated / Q000032:analysis*; D006863:Hydrogen-Ion Concentration; D006900:Hydroxylation; D007420:Intestine, Large / Q000737:chemistry; D008297:Male; D013058:Mass Spectrometry / Q000379:methods*; D008752:Methylene Chloride; D051381:Rats; D017208:Rats, Wistar; D017965:gamma-Linolenic Acid / Q000032:analysis / Q000378:metabolism
D004852:Epoxy Compounds; D005231:Fatty Acids, Unsaturated; D004281:Docosahexaenoic Acids; D016718:Arachidonic Acid; D008752:Methylene Chloride; D017965:gamma-Linolenic Acid; D003577:Cytochrome P-450 Enzyme System; D015118:Eicosapentaenoic Acid