Biliary proteins: Assessment of quantitative techniques and comparison in gallstone and nongallstone subjects

K. Yamazaki, S. P. Powers, N. F. LaRusso

Research output: Contribution to journalArticlepeer-review

55 Scopus citations


Although protein is the third most abundant solid in bile and is important in cholesterol crystal formation, methods for quantitating the concentration of total protein in bile have not been systematically evaluated. To establish a reliable protein assay for bile, we evaluated three protein assays (Lowry's method and the fluorescamine and Coomassie blue methods), and employed amino acid analysis as a reference technique. Large protein-to-protein variations were observed with the fluorescamine and Coomassie blue methods. Although all assays were affected by interfering substances, Lowry's method and the fluorescamine technique (after trichloroacetic acid precipitation and delipidation of bile) and the Coomassie blue method with native bile showed excellent correlations (P < 0.0001) with those obtained by amino acid analysis. Using these reliable protein assays, we examined gallbladder bile obtained at surgery from subjects with and without gallstones. No differences in the concentrations of total biliary proteins were observed among patients with cholesterol (n = 23) or pigment (n = 7) gallstones and subjects without gallstones (n = 10). Protein values obtained by amino acid analysis also did not differ among groups. As expected, bile from patients with cholesterol gallstones was supersaturated with cholesterol while bile from nongallstone subjects and those with pigment stones was unsaturated. These results indicate that it is not possible separate patients with and without gallstones on the basis of the total protein concentration of gallbladder bile.

Original languageEnglish (US)
Pages (from-to)1055-1063
Number of pages9
JournalJournal of Lipid Research
Issue number8
StatePublished - 1988

ASJC Scopus subject areas

  • Biochemistry
  • Endocrinology
  • Cell Biology


Dive into the research topics of 'Biliary proteins: Assessment of quantitative techniques and comparison in gallstone and nongallstone subjects'. Together they form a unique fingerprint.

Cite this