出版社：American Society for Biochemistry and Molecular Biology
摘要：Biliary lipids (bile salts, phospholipids, cholesterol, plantsterols) were determined in 89 vertebrate species (cartilaginousand bony fish, reptiles, birds, and mammals), and individualphospholipid classes were measured in 35 species. All samplescontained conjugated bile salts (C27 bile alcohol sulfates and/orN-acyl amidates of C27 and/or C24 bile acids). Phospholipidswere generally absent in the bile of cartilaginous fish andreptiles and were present in low amounts relative to bile saltsin bony fish and most birds. In mammals, the phospholipid-bilesalt ratio varied widely. The bile from species with low biliaryphospholipid-bile salt ratios often contained a high proportionof sphingomyelin, confirmed by HPLC-MS. In species with a highphospholipid-bile salt ratio, the predominant biliary phospholipidwas phosphatidylcholine (PC). The phospholipid-bile salt ratiocorrelated weakly with the calculated weighted hydrophobic indexvalue. Cholesterol was present in the bile of virtually allspecies, with plant sterols uniformly being present in onlytrace amounts. The cholesterol-bile salt ratio tended to behigher in mammals than in nonmammals, but bile of all specieswas unsaturated.
Thus, most nonmammalian vertebrates have relatively low levelsof biliary phospholipid and cholesterol, suggesting that cholesterolis eliminated predominantly as bile salts. Mammals have a higherphospholipid and cholesterol to bile salt ratio, with the dominantphospholipid being PC.Abbreviations: ABCG5, ATP binding cassette transporter G5; HI, hydrophobicity index; PC, phosphatidylcholine; RRT, relative retention time; WHI, weighted hydrophobicity index
Supplementary key words bile salts • cholesterol • gas chromatography • mass spectrometry • phosphatidylcholine • sphingomyelin
