Bidard J N, Rossi B, Renaud J F, Lazdunski M
Biochim Biophys Acta. 1984 Jan 11;769(1):245-52. doi: 10.1016/0005-2736(84)90029-4.
The electric organ of Electrophorus electricus contains substances which inhibit (Na+ + K+)-ATPase activity, the specific binding of [3H]ouabain to purified (Na+ + K+)-ATPase and 86Rb+ uptake by chick cardiac cells in culture. The active organic material was extracted from microsomal membranes. Its purification was carried out by chromatography on Sep-Pak C-18 and thin-layer chromatography. Reverse-phase liquid chromatography and mass spectrometry identified the active material as a mixture of unsaturated fatty acids. Linoleic (18:2), arachidonic (20:4), linolenic (18:3) and docosahexaenoic acids (22:6) contributed to about 60% of the total activity of the active material. The other active substances could be arachidonic analogs, since they have both a lipophilic and carboxylic character. Pure unsaturated fatty acids have been shown to be active in the different biological assays used to analyze the endogenous 'ouabain-like' activity. Linolenic, arachidonic and docosahexaenoic acids were the most active, whereas saturated fatty acids and glyceryl esters or methyl esters of unsaturated fatty acids were inactive. It is possible that in pathological situations in which the level of unsaturated fatty acids increases, these molecules may then act as physiological inhibitors of the sodium pump.
电鳗的电器官含有抑制（Na⁺ + K⁺）-ATP酶活性、[³H]哇巴因与纯化的（Na⁺ + K⁺）-ATP酶特异性结合以及培养的鸡心肌细胞对⁸⁶Rb⁺摄取的物质。活性有机物质是从微粒体膜中提取的。通过Sep-Pak C-18柱色谱和薄层色谱进行纯化。反相液相色谱和质谱鉴定活性物质为不饱和脂肪酸混合物。亚油酸（18:2）、花生四烯酸（20:4）、亚麻酸（18:3）和二十二碳六烯酸（22:6）约占活性物质总活性的60%。其他活性物质可能是花生四烯酸类似物，因为它们兼具亲脂性和羧基特性。已表明纯不饱和脂肪酸在用于分析内源性“类哇巴因”活性的不同生物学测定中具有活性。亚麻酸、花生四烯酸和二十二碳六烯酸活性最强，而饱和脂肪酸以及不饱和脂肪酸的甘油酯或甲酯则无活性。在不饱和脂肪酸水平升高的病理情况下，这些分子可能会作为钠泵的生理抑制剂发挥作用。
