Pope Edward C, Taylor Graham W, Rowley Andrew F
Centre for Sustainable Aquaculture Research, Department of Biological Sciences, University of Wales Swansea, Singleton Park, Swansea, SA2 8PP, UK.
Comp Biochem Physiol B Biochem Mol Biol. 2007 Aug;147(4):657-66. doi: 10.1016/j.cbpb.2007.04.006. Epub 2007 Apr 14.
Eicosanoids are a group of oxygenated fatty acid derivatives formed from C20 polyunsaturated fatty acids, including arachidonic and eicosapentaenoic acids. The potential of the coelomocytes of the starfish, Asterias rubens, to generate eicosanoids through the cyclooxygenase (COX) and lipoxygenase (LOX) pathways was investigated using reverse-phase high performance liquid chromatography, enzyme immunoassay and gas chromatography-mass spectrometry. The principal LOX product was identified as 8-hydroxyeicosatetraenoic acid (8-HETE) with 8-hydroxyeicosapentaenoic acid (8-HEPE) synthesised at significantly lower levels. No classical prostaglandins (PG), such as PGE2 or PGD2, were found to be generated by ionophore-challenged coelomocytes. Incubation of coelomocytes with lipopolysaccharides from either Escherichia coli or Salmonella abortus failed to induce an increase in generation of LOX products and the presence of 8-HETE (0-25 microM) had no significant effect on the in vitro phagocytic activity of Asterias coelomocytes. Neither indomethacin (a COX inhibitor) or esculetin (a LOX inhibitor) had any effect on the clearance of the bacterium, Vibrio splendidus, from the coelomic cavity of starfish suggesting that products of these enzymes are not involved in such coelomocyte responses to foreign particles.
类二十烷酸是一类由C20多不饱和脂肪酸形成的氧化脂肪酸衍生物，包括花生四烯酸和二十碳五烯酸。利用反相高效液相色谱、酶免疫测定和气相色谱 - 质谱联用技术，研究了海星（红海盘车）体腔细胞通过环氧化酶（COX）和脂氧合酶（LOX）途径生成类二十烷酸的潜力。主要的脂氧合酶产物被鉴定为8 - 羟基二十碳四烯酸（8 - HETE），而8 - 羟基二十碳五烯酸（8 - HEPE）的合成水平显著较低。未发现经离子载体刺激的体腔细胞产生诸如前列腺素E2（PGE2）或前列腺素D2（PGD2）等经典前列腺素。用来自大肠杆菌或流产沙门氏菌的脂多糖孵育体腔细胞，未能诱导脂氧合酶产物生成增加，并且8 - HETE（0 - 25微摩尔）的存在对红海盘车体腔细胞的体外吞噬活性没有显著影响。吲哚美辛（一种COX抑制剂）或七叶亭（一种LOX抑制剂）对海星体腔中灿烂弧菌的清除均无任何作用，这表明这些酶的产物不参与体腔细胞对外来颗粒的此类反应。
