Gordon J A, Heller S K, Kaduce T L, Spector A A
Department of Internal Medicine, University of Iowa College of Medicine, Iowa City 52242-1081.
J Biol Chem. 1994 Feb 11;269(6):4103-9.
Human skin fibroblasts labeled with [5,6,8,9,11,12,-14,15-3H]arachidonic acid produce a radioactive metabolite that has a shorter retention time on reverse-phase high-performance liquid chromatography than arachidonic acid. This product is not retained in the cells; it is released entirely into the extracellular fluid in a time-dependent manner. The metabolite does not cochromatograph with any of the eicosanoid standards, and its formation is not prevented by the addition of cyclooxygenase, lipoxygenase, or cytochrome P-450 inhibitors. The compound is not produced by fibroblasts labeled with [1-14C]arachidonic acid, suggesting that it is formed through an oxidative process. Chemical analyses indicated that the metabolite is 4,7,10-hexadecatrienoic acid (16:3). Peroxisome-deficient human skin fibroblasts did not produce 16:3, indicating that it probably is formed through peroxisomal beta-oxidation. Human umbilical vein endothelial cells and porcine pulmonary artery smooth muscle cells also release radioactive 16:3 following labeling with [3H]arachidonic acid. Therefore, the production of this metabolite is not limited only to fibroblasts. The fact that 16:3 is released into the extra-cellular fluid suggests that it may be a new type of lipid mediator derived from arachidonic acid, formed through a peroxisome-dependent oxidative process.
用[5,6,8,9,11,12,-14,15-³H]花生四烯酸标记的人皮肤成纤维细胞产生一种放射性代谢物，该代谢物在反相高效液相色谱上的保留时间比花生四烯酸短。这种产物不会保留在细胞内；它会以时间依赖性方式完全释放到细胞外液中。该代谢物与任何类二十烷酸标准品都不会共色谱，并且添加环氧化酶、脂氧化酶或细胞色素P-450抑制剂并不能阻止其形成。用[1-¹⁴C]花生四烯酸标记的成纤维细胞不会产生这种化合物，这表明它是通过氧化过程形成的。化学分析表明，该代谢物是4,7,10-十六碳三烯酸（16:3）。缺乏过氧化物酶体的人皮肤成纤维细胞不会产生16:3，这表明它可能是通过过氧化物酶体β-氧化形成的。用人脐静脉内皮细胞和猪肺动脉平滑肌细胞用[³H]花生四烯酸标记后，也会释放放射性16:3。因此，这种代谢物的产生并不局限于成纤维细胞。16:3释放到细胞外液中的事实表明，它可能是一种新型的源自花生四烯酸的脂质介质，通过依赖过氧化物酶体的氧化过程形成。
