title: The presence of ceramidase activity in liver nuclear membrane.
abstract: This report presents a demonstration of ceramidase activity in the nuclear membrane or envelope of mammalian livers. The products of ceramidase reaction were identified by means of TLC for released fatty acid and HPLC for sphingosine. The ceramidase activity was maximum over a broad neutral to alkaline region ranging from pH 7.0 to 8.8. This activity was inhibited by N-oleoylethanolamine known as a specific inhibitor for ceramidase and by anandamide to a similar extent. The enzymatic study suggests that the nuclear ceramidase has different properties from other ceramidase reported previously. As sphingomyelinase, one of enzymes involved in the sphingomyelin cycle, are known to be present in the nuclear membrane, it is now evident that at least two enzymes involved in the sphingomyelin cycle are present in the nuclear membrane.
authors.affiliation: Department of Health Chemistry, Faculty of Pharmaceutical Science, Niigata University of Pharmacy and Applied Life Sciences, 5-13-2 Kamishin-eicho, Niigata 950-2081, Japan. siraisi@niigata-pharm.ac.jp
authors.forename: Takayuki
authors.initials: T
authors.lastname: Shiraishi
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Imai
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Uda
mesh_terms: D000581:Amidohydrolases / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism*; D000818:Animals; D001095:Arachidonic Acids / Q000494:pharmacology; D002413:Cations, Divalent / Q000494:pharmacology; D055572:Ceramidases; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D063388:Endocannabinoids; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004983:Ethanolamines / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D066298:In Vitro Techniques; D008099:Liver / Q000201:enzymology*; D009685:Nuclear Envelope / Q000201:enzymology*; D009829:Oleic Acids; D053284:Polyunsaturated Alkamides; D051381:Rats; D013110:Sphingosine / Q000737:chemistry; D013552:Swine
chemical_list: D001095:Arachidonic Acids; D002413:Cations, Divalent; D063388:Endocannabinoids; D004791:Enzyme Inhibitors; D004983:Ethanolamines; D009829:Oleic Acids; D053284:Polyunsaturated Alkamides; C033595:N-oleoylethanolamine; D000581:Amidohydrolases; D055572:Ceramidases; D013110:Sphingosine; C078814:anandamide