Identification of 11-dehydrothromboxane B3 in human urine after administration of eicosapentaenoic acid

✍ Scribed by M. Ishibashi; Y. Ohyama; M. Mizugaki; N. Harima

• Publisher: John Wiley and Sons
• Year: 1990
• Tongue: English
• Weight: 233 KB
• Volume: 19
• Category: Article
• ISSN: 1076-5174
• DOI: 10.1002/bms.1200190610

✦ Synopsis

Much attention has recently been focused on the elucidation of the physiological role of the n-3 class of polyunsaturated fatty acids, especially eicosapentaenoic acid (EPA), because of its low correlation with cardiovascular diseases and myocardial infarction.' Previous studies have mentioned several competitive interactions between EPA and arachidonic acid (AA), some of which indicated the competitive inhibition of platelet cyclooxygenase activity and reduction of the formation of prothrombotic thromboxane A, (TXA,) from AA. In addition, anti-platelet aggregatory action of EPA is considered to form high levels of non-aggregating compound of thromboxane A, (TXA,), leading to an estimation that EPA could change the TXA/prostacyclin balance with a prostanoid formation from the dienoic and trienoic series., Fischer and Weber demonstrated that thromboxane B, (TXB,) would be formed ex vivo in collagen-stimulated human platelets from endogenous EPA after 25 days administration of cod-liver oil, and they predicted that TXB, may be formed in vitro., However, no attempts have been made to identify TXB, and/or its enzymatic metabolites in biological fluids after daily ingestion of dietary EPA or daily administration of EPA itself. FitzGerald et al. stated that, although thromboxane B, (TXB,) is a urinary metabolite of infused TXB, in man, the index is likely to reflect predominantly the renal TXA, generation under physiological condition^.^ 1 1 -Dehydro-TXB, , one major enzymatic metabolite of TXB,, has recently been considered to be a more reliable index of the endogenous TXA, biosynthesis than TXB,, which has been monitored as the stable hydrolysed product of TXA, . 5-7 It may therefore be of importance to identify the urinary metabolites of TXA, such as ll-dehydro-TXB, and/or 1 l-dehydro-2,3-dinor-TXB3, which are