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. 1971 Dec;50(12):2606–2613. doi: 10.1172/JCI106761

Bilirubin excretion in rats with normal and impaired bilirubin conjugation: effect of phenobarbital

Stephen H Robinson 1, Claudine Yannoni 1, Susumu Nagasawa 1
PMCID: PMC292210  PMID: 5129312

Abstract

The effect of phenobarbital on bilirubin excretion was studied in rats with different capacities for bilirubin conjugation. Drug treatment induced substantial increases in bilirubin UDP-glucuronyl transferase activity in the liver of both normal and heterozygous Gunn rats, but not homozygous Gunn rats in which enzyme activity is completely absent. However, enhancement of bilirubin excretion in vivo was observed only in heterozygous Gunn rats. In these animals the maximum capacity to excrete bilirubin into bile (Tmax), like the activity of the conjugating enzyme, was half normal; phenobarbital caused an increase in Tmax to levels characteristic of normal animals, with a twofold rise in the excretion of conjugated pigment. This appeared to be largely unrelated to enhancement of bile flow, and there was no stimulation of alternate pathways of bilirubin excretion.

Conjugated bilirubin was consistently recovered from the plasma and urine of both untreated normal and heterozygous Gunn rats infused with unconjugated pigment. The quantities thus recovered comprised a similar fraction of the total pigment conjugated in both types of animal. Moreover, there were linear correlations between Tmax and both the rate of bile flow and the activity of the conjugating enzyme over the range of values represented by control rats of both types. These findings suggest that the process by which conjugated bilirubin is secreted into the bile is closely related to conjugation and limits the final excretory rate at different levels of pigment excretion. The phenobarbital effect uniquely observed in heterozygous Gunn rats appears to be mediated primarily by enhancement of the limited capacity for bilirubin conjugation with an associated rise in functional secretory capacity.

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Selected References

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

  1. ARIAS I. M. A defect in microsomal function in nonhemolytic acholuric jaundice. J Histochem Cytochem. 1959 Jul;7(4):250–252. doi: 10.1177/7.4.250. [DOI] [PubMed] [Google Scholar]
  2. ARIAS I. M., JOHNSON L., WOLFSON S. Biliary excretion of injected conjugated and unconjugated bilirubin by normal and Gunn rats. Am J Physiol. 1961 May;200:1091–1094. doi: 10.1152/ajplegacy.1961.200.5.1091. [DOI] [PubMed] [Google Scholar]
  3. Arias I. M., Gartner L. M., Cohen M., Ezzer J. B., Levi A. J. Chronic nonhemolytic unconjugated hyperbilirubinemia with glucuronyl transferase deficiency. Clinical, biochemical, pharmacologic and genetic evidence for heterogeneity. Am J Med. 1969 Sep;47(3):395–409. doi: 10.1016/0002-9343(69)90224-1. [DOI] [PubMed] [Google Scholar]
  4. BILLING B. H., COLE P. G., LATHE G. H. The excretion of bilirubin as a diglucuronide giving the direct van den Bergh reaction. Biochem J. 1957 Apr;65(4):774–784. doi: 10.1042/bj0650774. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Barrett P. V., Mullins F. X., Berlin N. I. Studies on the biosynthesis production of bilirubin-C14: an improved method utilizing delta-aminolevulinic acid-4-C14 in dogs. J Lab Clin Med. 1966 Dec;68(6):905–912. [PubMed] [Google Scholar]
  6. Black M., Billing B. H. Hepatic bilirubin udp-glucuronyl transferase activity in liver disease and gilbert's syndrome. N Engl J Med. 1969 Jun 5;280(23):1266–1271. doi: 10.1056/NEJM196906052802303. [DOI] [PubMed] [Google Scholar]
  7. CAMPBELL R. M., CUTHBERTSON D. P., MATTHEWS C. M., MCFARLANE A. S. Behaviour of 14C- and 131I-labelled plasma proteins in the rat. Int J Appl Radiat Isot. 1956 Jul;1(1-2):66–84. doi: 10.1016/0020-708x(56)90020-5. [DOI] [PubMed] [Google Scholar]
  8. CARBONE J. V., GRODSKY G. M. Constitutional nonhemolytic hyperbilirubinemia in the rat: defect of bilirubin conjugation. Proc Soc Exp Biol Med. 1957 Mar;94(3):461–463. doi: 10.3181/00379727-94-22979. [DOI] [PubMed] [Google Scholar]
  9. Catz C., Yaffe S. J. Barbiturate enhancement of bilirubin conjugation and excretion in young and adult animals. Pediatr Res. 1968 Sep;2(5):361–370. doi: 10.1203/00006450-196809000-00005. [DOI] [PubMed] [Google Scholar]
  10. Conney A. H. Pharmacological implications of microsomal enzyme induction. Pharmacol Rev. 1967 Sep;19(3):317–366. [PubMed] [Google Scholar]
  11. Crigler J. F., Jr, Gold N. I. Effect of sodium phenobarbital on bilirubin metabolism in an infant with congenital, nonhemolytic, unconjugated hyperbilirubinemia, and kernicterus. J Clin Invest. 1969 Jan;48(1):42–55. doi: 10.1172/JCI105973. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. DEWEY W. C. Vascular-extravascular exchange of II31 plasma proteins in the rat. Am J Physiol. 1959 Aug;197:423–431. doi: 10.1152/ajplegacy.1959.197.2.423. [DOI] [PubMed] [Google Scholar]
  13. DeLeon A., Gartner L. M., Arias I. M. The effect of phenobarbital on hyperbilirubinemia in glucuronyl transferase deficient rats. J Lab Clin Med. 1967 Aug;70(2):273–278. [PubMed] [Google Scholar]
  14. FULOP M., SANDSON J., BRAZEAU P. DIALYZABILITY, PROTEIN BINDING, AND RENAL EXCRETION OF PLASMA CONJUGATED BILIRUBIN. J Clin Invest. 1965 Apr;44:666–680. doi: 10.1172/JCI105179. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. HARGREAVES T., LATHE G. H. INHIBITORY ASPECTS OF BILE SECRETION. Nature. 1963 Dec 21;200:1172–1176. doi: 10.1038/2001172a0. [DOI] [PubMed] [Google Scholar]
  16. HARGREAVES T. THE ESTIMATION OF BILIRUBIN IN LIVER. Clin Chim Acta. 1965 Mar;11:278–280. doi: 10.1016/0009-8981(65)90075-6. [DOI] [PubMed] [Google Scholar]
  17. Halac E., Jr, Sicignano C. Re-evaluation of the influence of sex, age pregnancy, and phenobarbital on the activity of UDP-glucuronyl transferase in rat liver. J Lab Clin Med. 1969 Apr;73(4):677–685. [PubMed] [Google Scholar]
  18. Klaassen C. D., Plaa G. L. Studies on the mechanism of phenobarbital-enhanced sulfobromophthalein disappearance. J Pharmacol Exp Ther. 1968 Jun;161(2):361–366. [PubMed] [Google Scholar]
  19. 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]
  20. Lester R., Klein P. D. Biosynthesis of tritiated bilirubin and studies of its excretion in the rat. J Lab Clin Med. 1966 Jun;67(6):1000–1012. [PubMed] [Google Scholar]
  21. O'Máille E. R., Richards T. G., Short A. H. Factors determining the maximal rate of organic anion secretion by the liver and further evidence on the hepatic site of action of the hormone secretin. J Physiol. 1966 Oct;186(2):424–438. doi: 10.1113/jphysiol.1966.sp008044. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. OSTROW J. D., HAMMAKER L., SCHMID R. The preparation of crystalline bilirubin-C14. J Clin Invest. 1961 Aug;40:1442–1452. doi: 10.1172/JCI104375. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Reyes H., Levi A. J., Gatmaitan Z., Arias I. M. Organic anion-binding protein in rat liver: drug induction and its physiologic consequence. Proc Natl Acad Sci U S A. 1969 Sep;64(1):168–170. doi: 10.1073/pnas.64.1.168. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Roberts R. J., Klaassen C. D., Plaa G. L. Maximum biliary excretion of bilirubin and sulfobromophthalein during anesthesia-induced alteration of rectal temperature. Proc Soc Exp Biol Med. 1967 May;125(1):313–316. doi: 10.3181/00379727-125-32080. [DOI] [PubMed] [Google Scholar]
  25. Roberts R. J., Plaa G. L. Effect of phenobarbital on the excretion of an exogenous bilirubin load. Biochem Pharmacol. 1967 May;16(5):827–835. doi: 10.1016/0006-2952(67)90055-x. [DOI] [PubMed] [Google Scholar]
  26. Robinson S. H. Increased bilirubin conjugation in heterozygous Gunn rats treated with phenobarbital. Nature. 1969 Jun 7;222(5197):990–991. doi: 10.1038/222990a0. [DOI] [PubMed] [Google Scholar]
  27. Robinson S. H. Production and excretion of bilirubin in Gunn rats treated with phenobarbital. Proc Soc Exp Biol Med. 1971 Oct;138(1):281–284. doi: 10.3181/00379727-138-35879. [DOI] [PubMed] [Google Scholar]
  28. Robinson S. H., Tsong M., Brown B. W., Schmid R. The sources of bile pigment in the rat: studies of the "early labeled" fraction. J Clin Invest. 1966 Oct;45(10):1569–1586. doi: 10.1172/JCI105463. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Rugstad H. E., Robinson S. H., Yannoni C., Tashjian A. H., Jr Metabolism of bilirubin by a clonal strain of rat hepatoma cells. J Cell Biol. 1970 Dec;47(3):703–710. doi: 10.1083/jcb.47.3.703. [DOI] [PMC free article] [PubMed] [Google Scholar]
  30. SCHALM L., WEBER A. P. JAUNDICE WITH CONJUGATED BILIRUBIN IN HYPERHAEMOLYSIS. Acta Med Scand. 1964 Nov;176:549–553. doi: 10.1111/j.0954-6820.1964.tb00657.x. [DOI] [PubMed] [Google Scholar]
  31. SCHMID R., AXELROD J., HAMMAKER L., SWARM R. L. Congenital jaundice in rats, due to a defect in glucuronide formation. J Clin Invest. 1958 Aug;37(8):1123–1130. doi: 10.1172/JCI103702. [DOI] [PMC free article] [PubMed] [Google Scholar]
  32. SCHMID R., HAMMAKER L. METABOLISM AND DISPOSITION OF C14-BILIRUBIN IN CONGENITAL NONHEMOLYTIC JAUNDICE. J Clin Invest. 1963 Nov;42:1720–1734. doi: 10.1172/JCI104858. [DOI] [PMC free article] [PubMed] [Google Scholar]
  33. SPERBER I. Secretion of organic anions in the formation of urine and bile. Pharmacol Rev. 1959 Mar;11(1):109–134. [PubMed] [Google Scholar]
  34. Schmid R., Marver H. S., Hammaker L. Enhanced formation of rapidly labelled bilirubin by phenobarbital: hepatic microsomal cytochromes as a possible source. Biochem Biophys Res Commun. 1966 Aug 12;24(3):319–328. doi: 10.1016/0006-291x(66)90158-6. [DOI] [PubMed] [Google Scholar]
  35. TISDALE W. A., KLATSKIN G., KINSELLA E. D. The significance of the direct-reacting fraction of serum bilirubin in hemolytic jaundice. Am J Med. 1959 Feb;26(2):214–227. doi: 10.1016/0002-9343(59)90310-9. [DOI] [PubMed] [Google Scholar]
  36. Van Roy F. P., Heirwegh K. P. Determination of bilirubin glucuronide and assay of glucuronyltransferase with bilirubin as acceptor. Biochem J. 1968 Apr;107(4):507–518. doi: 10.1042/bj1070507. [DOI] [PMC free article] [PubMed] [Google Scholar]
  37. WEBER A. P., SCHALM L. Quantitative separation and determination of bilirubin and conjugated bilirubin in human serum. Clin Chim Acta. 1962 Nov;7:805–810. doi: 10.1016/0009-8981(62)90063-3. [DOI] [PubMed] [Google Scholar]
  38. WEINBREN K., BILLING B. H. Hepatic clearance of bilirubin as an index of cellular function in the regenerating rat liver. Br J Exp Pathol. 1956 Apr;37(2):199–204. [PMC free article] [PubMed] [Google Scholar]
  39. Whelan G., Combes B. Depression of biliary excretion of infused bilirubin in rats and guinea pigs by bile. Am J Physiol. 1971 Mar;220(3):683–687. doi: 10.1152/ajplegacy.1971.220.3.683. [DOI] [PubMed] [Google Scholar]
  40. Yaffe S. J., Levy G., Matsuzawa T., Baliah T. Enhancement of glucuronide-conjugating capacity in a hyperbilirubinemic infant due to apparent enzyme induction by phenobarbital. N Engl J Med. 1966 Dec 29;275(26):1461–1466. doi: 10.1056/NEJM196612292752602. [DOI] [PubMed] [Google Scholar]

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