TY - JOUR
T1 - Bilirubin inhibits calcium carbonate precipitation in gallbladder bile
AU - Tam, Michael L.
AU - Fox-Talbot, M. Karen
AU - Pitt, Henry A.
AU - Lillemoe, Keith D.
AU - Lipsett, Pamela A.
N1 - Funding Information:
Supported by Sandoz Clinician Scientist Award and National Institutes of Health grants 1-R29DK 41889 and RO1DK 44979. Accepted for publication Jan. 16, 1995. Reprint requests: Pamela Lipsett, MD, Blalock 605, The Johns Hopkins Hospital, 600 N. Wolfe St., Baltimore, MD 212874605. Copyright 9 1995 by Mosby-Year Book, Inc. 0039-6060/95/$3.00 + 0 11/56/63913
PY - 1995/9
Y1 - 1995/9
N2 - Background. Previous studies have shown that human bile contains one or more factors that inhibitthe precipitation of calcium carbonate from supersaturated solutions of calcium chloride and sodium bicarbonate. Lower concentrations of this factor have been observed in the gallbladder bile of patients with calcified gallstones. We hypothesized that gallbladder bile contains factors that inhibit calcium carbonate and these factors are present in varying concentrations in normal persons and in patients with cholesterol gallstones with and without calcium carbonate. Methods. Gallbladder bile of patients without gallstones (n=8) and of patients with cholesterolgallstones containing either calcium carbonate (n=8) or other calcium salts (n=8) was assayed for calcium carbonate inhibition. Individual components of bile (bilirubin, phospholipid, bile salts, and albumin) were tested in different concentrations in the same assay system. In addition, samples of model bile were tested. Results. An inhibitory factor for calcium carbonate precipitation was present within all human gallbladder bile, irrespective of the absence, presence, or type of gallstones. The addition of a bilirubin-albumin solution to a supersaturated solution of calcium chloride and sodium bicarbonate entirely blocked precipitation of calcium carbonate from solution. In addition, serial dilutions of bilirubin exhibited a linear response between bilirubin concentration and inhibitory effect. Model bile and phospholipid dissolved in sodium taurocholate also exhibited a modest inhibitory effect on calcium carbonate precipitation. Conclusion. We conclude that bilirubin, cholesterol, and phospholipids incrementally interfere withcalcium carbonate precipitation in supersaturated solutions through the preferential formation of a soluble calcium complex.
AB - Background. Previous studies have shown that human bile contains one or more factors that inhibitthe precipitation of calcium carbonate from supersaturated solutions of calcium chloride and sodium bicarbonate. Lower concentrations of this factor have been observed in the gallbladder bile of patients with calcified gallstones. We hypothesized that gallbladder bile contains factors that inhibit calcium carbonate and these factors are present in varying concentrations in normal persons and in patients with cholesterol gallstones with and without calcium carbonate. Methods. Gallbladder bile of patients without gallstones (n=8) and of patients with cholesterolgallstones containing either calcium carbonate (n=8) or other calcium salts (n=8) was assayed for calcium carbonate inhibition. Individual components of bile (bilirubin, phospholipid, bile salts, and albumin) were tested in different concentrations in the same assay system. In addition, samples of model bile were tested. Results. An inhibitory factor for calcium carbonate precipitation was present within all human gallbladder bile, irrespective of the absence, presence, or type of gallstones. The addition of a bilirubin-albumin solution to a supersaturated solution of calcium chloride and sodium bicarbonate entirely blocked precipitation of calcium carbonate from solution. In addition, serial dilutions of bilirubin exhibited a linear response between bilirubin concentration and inhibitory effect. Model bile and phospholipid dissolved in sodium taurocholate also exhibited a modest inhibitory effect on calcium carbonate precipitation. Conclusion. We conclude that bilirubin, cholesterol, and phospholipids incrementally interfere withcalcium carbonate precipitation in supersaturated solutions through the preferential formation of a soluble calcium complex.
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U2 - 10.1016/S0039-6060(05)80369-1
DO - 10.1016/S0039-6060(05)80369-1
M3 - Article
C2 - 7652689
AN - SCOPUS:0029090158
SN - 0039-6060
VL - 118
SP - 524
EP - 530
JO - Surgery
JF - Surgery
IS - 3
ER -