Skip to main content
PMC home page
The Journal of Clinical Investigation logoLink to The Journal of Clinical Investigation
. 1975 Jan;55(1):105–114. doi: 10.1172/JCI107900

Mechanism of secretion of biliary lipids. I. Role of bile canalicular and microsomal membranes in the synthesis and transport of biliary lecithin and cholesterol.

D H Gregory, Z R Vlahcevic, P Schatzki, L Swell
PMCID: PMC301722  PMID: 1109174

Abstract

The role of bile canalicular and microsomal membranes in the synthesis and transport of biliary lipids was investigated by using the isolated perfused rat liver model. Labeled lecithin precursors ((3H)-palmitic acid, (14C)linoleic acid, (3H)choline, and 32PO4) and a cholesterol precursor ((3H)mevalonic acid) were administered with and without sodium taurocholate. The incorporation pattern of these labeled precursors into linoleyl and arachidonyl lecithins and cholesterol fractions of microsomes, bile canaliculi, and bile were examined at 30-min intervals up to 90 min. Marker enzymes and electron microscopy indicated that isolated subfractions of plasma membranes were enriched with bile canaliculi (less than 10 percent microsomal contamination). Taurocholate significantly stimulated the incorporation of 32PO4, (3H)choline, (3H)palmitic acid, and (14C)linoleic acid into linoleyl and arachidonyl lecithin with parallel incorporation curves for microsomal and bile canalicular membranes throughout the 90-min study period. During the 30-60-min period, however, these same lecithin fractions in bile significantly exceeded the specific activity of the membrane lecithins. The enzyme CDP-choline diglyceride transferase was virtually absent from canaliculi relative to microsomes, indicating that canaliculi lack the capacity for de novo lecithin synthesis. Incorporation of (3H)mevalonic acid into membranous and biliary cholesterol followed a pattern similar to that for lecithin. These data provide evidence that (a) biliary lecithin and cholesterol are derived from a microsomal subpool regulated by the flux of enterohepatic bile acids, (b) the role of the bile canalicular membranes with respect to biliary lipids is primarily transport rather than synthesis, and (c) lecithin and cholesterol are transported together from microsomes to bile. The findings are consistent with the existence of a cytoplasmic lipid complex within the hepatocyte which is actively involved in the intermembrane transport of biliary lipid.

Full text

PDF
105

Images in this article

109Image
on p.109

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Admirand W. H., Small D. M. The physicochemical basis of cholesterol gallstone formation in man. J Clin Invest. 1968 May;47(5):1043–1052. doi: 10.1172/JCI105794. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Akiyama M., Sakagami T. Exchange of mitochondrial lecithin and cephalin with those in rat liver microsomes. Biochim Biophys Acta. 1969 Jul 29;187(1):105–112. [PubMed] [Google Scholar]
  3. Arvidson G. A. Structural and metabolic heterogeneity of rat liver glycerophosphatides. Eur J Biochem. 1968 May;4(4):478–486. doi: 10.1111/j.1432-1033.1968.tb00237.x. [DOI] [PubMed] [Google Scholar]
  4. BALINT J. A., KYRIAKIDES E. C., SPITZER H. L., MORRISON E. S. LECITHIN FATTY ACID COMPOSITION IN BILE AND PLASMA OF MAN, DOGS, RATS, AND OXEN. J Lipid Res. 1965 Jan;6:96–99. [PubMed] [Google Scholar]
  5. BARTLETT G. R. Phosphorus assay in column chromatography. J Biol Chem. 1959 Mar;234(3):466–468. [PubMed] [Google Scholar]
  6. Balint J. A., Beeler D. A., Kyriakides E. C., Treble D. H. The effect of bile salts upon lecithin synthesis. J Lab Clin Med. 1971 Jan;77(1):122–133. [PubMed] [Google Scholar]
  7. Balint J. A., Beeler D. A., Treble D. H., Spitzer H. L. Studies in the biosynthesis of hepatic and biliary lecithins. J Lipid Res. 1967 Sep;8(5):486–493. [PubMed] [Google Scholar]
  8. Bell C. C., Jr, Vlahcevic Z. R., Prazich J., Swell L. Evidence that a diminished bile acid pool precedes the formation of cholesterol gallstones in man. Surg Gynecol Obstet. 1973 Jun;136(6):961–965. [PubMed] [Google Scholar]
  9. Bell C. C., Jr, Vlahcevic Z. R., Swell L. Alterations in the lipids of human hepatic bile after the oral administration of bile salts. Surg Gynecol Obstet. 1971 Jan;132(1):36–42. [PubMed] [Google Scholar]
  10. Danzinger R. C., Hofmann A. F., Thistle J. L., Schoenfield L. J. Effect of oral chenodeoxycholic acid on bile acid kinetics and biliary lipid composition in women with cholelithiasis. J Clin Invest. 1973 Nov;52(11):2809–2821. doi: 10.1172/JCI107477. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. De Kruyff B., Van Golde L. M., Van Deenen L. L. Utilization of diacylglycerol species by cholinephosphotransferase, ethanolaminephosphotransferase and diacylglycerol acyltransferase in rat liver microsomes. Biochim Biophys Acta. 1970 Sep 8;210(3):425–435. doi: 10.1016/0005-2760(70)90038-x. [DOI] [PubMed] [Google Scholar]
  12. Emmelot P., Bos C. J. Studies on plasma membranes. 3. Mg2+-ATPase,(Na+-K+-Mg2+)-ATPase and 5'-nucleotidase activity of plasma membranes isolated from rat liver. Biochim Biophys Acta. 1966 Jul 13;120(3):369–382. doi: 10.1016/0926-6585(66)90304-9. [DOI] [PubMed] [Google Scholar]
  13. Entemnan C., Holloway R. J., Albright M. L., Leong G. F. Bile acids and lipid metabolism. I. Stimulation of bile lipid excretion by various bile acids. Proc Soc Exp Biol Med. 1968 Apr;127(4):1003–1006. doi: 10.3181/00379727-127-32855. [DOI] [PubMed] [Google Scholar]
  14. FOLCH J., LEES M., SLOANE STANLEY G. H. A simple method for the isolation and purification of total lipides from animal tissues. J Biol Chem. 1957 May;226(1):497–509. [PubMed] [Google Scholar]
  15. HIRSCH J., AHRENS E. H., Jr The separation of complex lipide mixtures by the use of silicic acid chromatography. J Biol Chem. 1958 Aug;233(2):311–20. [PubMed] [Google Scholar]
  16. KAY R. E., ENTENMAN C. Stimulation of taurocholic acid synthesis and biliary excretion of lipids. Am J Physiol. 1961 Apr;200:855–859. doi: 10.1152/ajplegacy.1961.200.4.855. [DOI] [PubMed] [Google Scholar]
  17. Kanoh H. Biosynthesis of molecular species of phosphatidyl choline and phosphatidyl ethanolamine from radioactive precursors in rat liver slices. Biochim Biophys Acta. 1969 Jun 10;176(4):756–763. [PubMed] [Google Scholar]
  18. LOWRY O. H., ROSEBROUGH N. J., FARR A. L., RANDALL R. J. Protein measurement with the Folin phenol reagent. J Biol Chem. 1951 Nov;193(1):265–275. [PubMed] [Google Scholar]
  19. Lee T. C., Snyder F. Phospholipid metabolism in rat liver endoplasmic reticulum. Structural analyses, turnover studies and enzymic activities. Biochim Biophys Acta. 1973 Jan 2;291(1):71–82. doi: 10.1016/0005-2736(73)90061-8. [DOI] [PubMed] [Google Scholar]
  20. Nilsson S., Scherstén T. Importance of bile acids for phospholipid secretion into human hepatic bile. Gastroenterology. 1969 Nov;57(5):525–532. [PubMed] [Google Scholar]
  21. SCHWARTZ M. K., BODANSKY O. Glycolytic and related enzymes. Methods Med Res. 1961;9:5–23. [PubMed] [Google Scholar]
  22. Sarzala M. G., Van Golde L. M., De Kruyff B., Van Deenen L. L. The intramitochondrial distribution of some enzymes involved in the biosynthesis of rat-liver phospholipids. Biochim Biophys Acta. 1970 Feb 10;202(1):106–119. doi: 10.1016/0005-2760(70)90222-5. [DOI] [PubMed] [Google Scholar]
  23. Scallen T. J., Schuster M. W., Dhar A. K. Evidence for a noncatalytic carrier protein in cholesterol biosynthesis. J Biol Chem. 1971 Jan 10;246(1):224–230. [PubMed] [Google Scholar]
  24. Skipski V. P., Peterson R. F., Barclay M. Quantitative analysis of phospholipids by thin-layer chromatography. Biochem J. 1964 Feb;90(2):374–378. doi: 10.1042/bj0900374. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Song C. S., Rubin W., Rifkind A. B., Kappas A. Plasma membranes of the rat liver. Isolation and enzymatic characterization of a fraction rich in bile canaliculi. J Cell Biol. 1969 Apr;41(1):124–132. doi: 10.1083/jcb.41.1.124. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Sundler R., Arvidson G., Akesson B. Pathways for the incorporation of choline into rat liver phosphatidylcholines in vivo. Biochim Biophys Acta. 1972 Dec 8;280(4):559–568. doi: 10.1016/0005-2760(72)90136-1. [DOI] [PubMed] [Google Scholar]
  27. Swell L., Bell C. C., Jr, Entenman C. Bile acids and lipid metabolism. 3. Influence of bile acids on phospholipids in liver and bile of the isolated perfused dog liver. Biochim Biophys Acta. 1968 Oct 22;164(2):278–284. [PubMed] [Google Scholar]
  28. Swell L., Bell C. C., Jr, Vlahcevic Z. R. Relationship of bile acid pool size to biliary lipid excretion and the formation of lithogenic bile in man. Gastroenterology. 1971 Nov;61(5):716–722. [PubMed] [Google Scholar]
  29. Swell L., Entenman C., Leong G. F., Holloway R. J. Bile acids and lipid metabolism. IV. Influence of bile acids on biliary and liver organelle phospholipids and cholesterol. Am J Physiol. 1968 Dec;215(6):1390–1396. doi: 10.1152/ajplegacy.1968.215.6.1390. [DOI] [PubMed] [Google Scholar]
  30. Swell L., Law M. D. Release of lipoprotein cholesterol esters by the isolated perfused rat liver. Biochim Biophys Acta. 1971 Mar 16;231(2):302–313. doi: 10.1016/0005-2760(71)90143-3. [DOI] [PubMed] [Google Scholar]
  31. Trewhella M. A., Collins F. D. Pathways of phosphatidylcholine biosynthesis in rat liver. Biochim Biophys Acta. 1973 Jan 19;296(1):51–61. doi: 10.1016/0005-2760(73)90042-8. [DOI] [PubMed] [Google Scholar]
  32. Vlahcevic Z. R., Bell C. C., Jr, Buhac I., Farrar J. T., Swell L. Diminished bile acid pool size in patients with gallstones. Gastroenterology. 1970 Aug;59(2):165–173. [PubMed] [Google Scholar]
  33. Wheeler H. O., King K. K. Biliary excretion of lecithin and cholesterol in the dog. J Clin Invest. 1972 Jun;51(6):1337–1350. doi: 10.1172/JCI106930. [DOI] [PMC free article] [PubMed] [Google Scholar]
  34. Widnell C. C., Unkeless J. C. Partial purification of a lipoprotein with 5'-nucleotidase activity from membranes of rat liver cells. Proc Natl Acad Sci U S A. 1968 Nov;61(3):1050–1057. doi: 10.1073/pnas.61.3.1050. [DOI] [PMC free article] [PubMed] [Google Scholar]
  35. Wykle R. L., Blank M. L., Snyder F. The enzymic incorporation of arachidonic acid into ether-containing choline and ethanolamie phosphoglycerides by deacylation-acylation reactions. Biochim Biophys Acta. 1973 Oct 17;326(1):26–33. doi: 10.1016/0005-2760(73)90024-6. [DOI] [PubMed] [Google Scholar]
  36. Young D. L., Hanson K. C. Effect of bile salts on hepatic phosphatidylcholine synthesis and transport into rat bile. J Lipid Res. 1972 Mar;13(2):244–252. [PubMed] [Google Scholar]

Articles from Journal of Clinical Investigation are provided here courtesy of American Society for Clinical Investigation

RESOURCES