Abstract
Mixed lipid micelles were isolated from rat bile on taurocholate-equilibrated Sephadex G100 and G200 columns (5-60 mM) to study relationships between lipids and other constituents of bile. Phospholipid, cholesterol, and a bile salt peak co-eluted as mixed micelles at all taurocholate concentrations. The micellar radius, derived from the elution profile, increased progressively from approximately 1.6 nm to approximately 3.5 nm when the column taurocholate concentration was reduced from 40-60 mM to 5 mM (the physiological range for rat bile). Biliary bile pigment and bromsulphthalein, added in vivo, eluted as self-aggregates that were smaller than the lipid micelles. In contrast, on bromsulphthalein-equilibrated columns, unconjugated bromsulphthalein associated weakly with lipid micelles but this association accounted for less than 10% of the unconjugated dye in bile. No associations were found between lipid and proteins when SDS-polyacrylamide gel electrophoretic polypeptide patterns of column fractions were compared with the lipid elution profiles at different taurocholate concentrations. Two high molecular weight protein aggregates were demonstrated in bile (greater than 222,000 Mr) by Sephadex G200 chromatography. These studies provide a reliable estimate of rat bile lipid micelle size and suggest that bile pigment, bromsulphthalein and proteins do not form strong associations with biliary mixed micelles but exist in bile predominantly as self-aggregates.
Highlights
Mixed lipid micelles were isolated from rat bile on taurocholate-equilibratedSephadex GlOO and G200 columns (5-60 mM) to studyrelationshipsbetween lipids and other constituents of bile
We have examined the interactions between biliary lipids, organic anions, and proteins in rat bile utilizing gel filtration chromatography with biliary mixed micelles but exist in bile predominantly as as the major technique.Bile salt solutions were usedfor self-aggregates.-Reuben, A., K.E
Evidence is presented that suggests that organic anions and most of the biliary proteins are present in bile as aggregates and do not form strong associationswith lipid micelles inthe physiological concentrations of bile salts used in these studies
Summary
Mixed lipid micelles were isolated from rat bile on taurocholate-equilibratedSephadex GlOO and G200 columns (5-60 mM) to studyrelationshipsbetween lipids and other constituents of bile. The micellar radius, derived from the elution profile, that thebiliary secretion of many low molecular weight organic compounds is enhanced by self-aggregation or by their association with the mixed micelles in bile [9, 10]. The formation of self-aggregates is well documented for organic anions such as bilirubin and increased progressively from "1.6 nm to "3.5 nm when the bromsulphthalein (BSP) [10,11,12], the association becolumn taurocholate concentration was reduced from 40-60 mM to 5 mM (the physiological range for rat bile). We have examined the interactions between biliary lipids, organic anions, and proteins in rat bile utilizing gel filtration chromatography with biliary mixed micelles but exist in bile predominantly as as the major technique.Bile salt solutions were usedfor self-aggregates.-Reuben, A., K.E. Howell, and J.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
