title: Identification of 11,13-dihydroxy-14-octadecaenoic acid as a circulating Na+/K(+)-ATPase inhibitor.
abstract: Two digitalis-like compounds (DLC) were purified to homogeneity from bovine plasma. The purification procedure consisted of organic extractions and batch chromatography followed by three subsequent separations using reverse-phase high-performance liquid chromatography. The presence of a DLC in the different fractions was monitored by their ability to inhibit (a) [3H]ouabain binding to rat brain synaptosomes, and (b) microsomal Na+/K(+)-ATPase activity. Using mass spectrometry and nuclear magnetic resonance spectroscopy the structure of one of the DLCs was identified as 11,13-dihydroxy-14-octadecaenoic acid. It is suggested that this new hydroxy, unsaturated, fatty acid derivative may regulate Na+/K(+)-ATPase activity under some physiological and pathological conditions.
authors.affiliation: Department of Physiology, Hebrew University-Hadassah Medical School, Jerusalem, Israel.
authors.forename: D
authors.initials: D
authors.lastname: Lichtstein
authors.forename: S
authors.initials: S
authors.lastname: Samuelov
authors.forename: I
authors.initials: I
authors.lastname: Gati
authors.forename: A M
authors.initials: AM
authors.lastname: Felix
authors.forename: T F
authors.initials: TF
authors.lastname: Gabriel
authors.forename: J
authors.initials: J
authors.lastname: Deutsch
mesh_terms: D000818:Animals; D001921:Brain / Q000378:metabolism; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008861:Microsomes / Q000187:drug effects / Q000201:enzymology; D009829:Oleic Acids / Q000097:blood* / Q000737:chemistry; D010042:Ouabain / Q000378:metabolism; D011485:Protein Binding / Q000187:drug effects; D000254:Sodium-Potassium-Exchanging ATPase / Q000037:antagonists & inhibitors*
chemical_list: D009829:Oleic Acids; C067685:11,13-dihydroxy-14-octadecaenoic acid; D010042:Ouabain; D000254:Sodium-Potassium-Exchanging ATPase