title: Free ceramide, sphingomyelin, and glucosylceramide of isolated rat intestinal cells.
abstract: Free ceramide, glucosylceramide, and sphingomyelin were isolated from mature cells of adult rat small intestine. Free ceramide and ceramide cleaved from sphingomyelin by enzymatic hydrolysis were fractionated by thin-layer chromatography on borate-impregnated silica gel plates. Sphingoid bases were characterized by gas-liquid chromatography of aldehydes formed upon periodate oxidation. Fatty acids were quantified as methyl esters. Ceramide structures were confirmed by direct-inlet mass spectrometry. Free ceramide was found to contain two major long-chain bases in nearly equal quantity: sphingosine, mainly linked to palmitic acid, and 4D-hydroxysphinganine associated with C20 to C24 fatty acids, 22% being hydroxylated. Sphinganine occurred as a minor component linked to nonhydroxy fatty acids. Sphingomyelin contained the three long-chain bases and 63% of its ceramide was N-palmitoyl-sphingosine. Mass spectrometry of glucosylceramide confirmed 4D-hydroxyshingamine as the major sphingoid base associated preferentially with longer chain hydroxy fatty acids.
mesh_terms: D000818:Animals; D002518:Ceramides / Q000032:analysis*; D002554:Cerebrosides / Q000032:analysis*; D002849:Chromatography, Gas; D005227:Fatty Acids / Q000032:analysis; D005963:Glucosylceramides / Q000032:analysis*; D066298:In Vitro Techniques; D007421:Intestine, Small / Q000032:analysis*; D008297:Male; D013058:Mass Spectrometry; D051381:Rats; D013109:Sphingomyelins / Q000032:analysis*
chemical_list: D002518:Ceramides; D002554:Cerebrosides; D005227:Fatty Acids; D005963:Glucosylceramides; D013109:Sphingomyelins