Thomson M, al-Hassan J M, al-Saleh J, Fayad S, Ali M
Department of Biochemistry, Faculty of Science, Kuwait University, Safat, Kuwait.
Comp Biochem Physiol B Biochem Mol Biol. 1998 Apr;119(4):639-46. doi: 10.1016/s0305-0491(98)00039-x.
The ability to synthesise prostaglandins and thromboxane from 14C-labelled arachidonic acid was investigated in 11 species of fish from the Arabian Gulf. Cyclooxygenase activity was assessed in washed whole blood cells. Arachidonic acid and its metabolites were extracted and separated on silicic acid columns and thin layer chromatography (silica gel G). Total capacity to convert [14C]arachidonic acid to prostanoids varied from 1 to 35% among the 11 fish species studied. Gray shark (Chiloscyllium griseum) blood cells had the highest capacity (37 +/- 0.4%) to convert arachidonate into prostanoids and two species of catfish (Arius bilineatus and A. thalassinus) exhibited greater than 10% capacity to convert [14C]arachidonate into prostanoids. The major prostanoid synthesised by the two catfish (A. bilineatus and A thalassinus) was 6-keto PGF1 alpha, a stable metabolite of prostacyclin, PGI2. In contrast, A. teunispinis synthesised thromboxane B2, a stable metabolite of thromboxane A2. Thromboxane B2 (TXB2) was the major product synthesised by all three species of shark studied (Chil. griseum, Carcharhinus plumbeus, Carch. melanopterus), with 6-keto PGF1 alpha a minor product. Other fish studied showed a varied pattern of prostanoid synthesis. The synthesis of these prostanoids was almost completely blocked by preincubation of the whole blood cells from catfish and shark with indomethacin (0.5 microM) suggesting the involvement of cyclooxygenase-mediated prostanoid synthesis.
对来自阿拉伯湾的11种鱼类合成前列腺素和血栓素的能力进行了研究，以14C标记的花生四烯酸作为底物。通过检测洗涤后的全血细胞中的环氧化酶活性来评估其活性。花生四烯酸及其代谢产物通过硅酸柱和薄层层析（硅胶G）进行提取和分离。在所研究的11种鱼类中，将[14C]花生四烯酸转化为前列腺素的总能力在1%至35%之间。灰斑竹鲨（Chiloscyllium griseum）血细胞将花生四烯酸转化为前列腺素的能力最高（37±0.4%），两种鲶鱼（双线海鲶Arius bilineatus和泰氏海鲶A. thalassinus）将[14C]花生四烯酸转化为前列腺素的能力大于10%。两种鲶鱼（双线海鲶和泰氏海鲶）合成的主要前列腺素是6-酮-PGF1α，它是前列环素PGI2的稳定代谢产物。相比之下，特氏海鲶（A. teunispinis）合成血栓素B2，它是血栓素A2的稳定代谢产物。血栓素B2（TXB2）是所研究的三种鲨鱼（灰斑竹鲨、铅灰真鲨Carcharhinus plumbeus、黑鳍真鲨Carch. melanopterus）合成的主要产物，6-酮-PGF1α是次要产物。其他研究的鱼类显示出不同的前列腺素合成模式。鲶鱼和鲨鱼的全血细胞与吲哚美辛（0.5微摩尔）预孵育后，这些前列腺素的合成几乎完全被阻断，这表明环氧化酶介导的前列腺素合成参与其中。
