Abstract
This study contains a pharmacokinetic analysis on the efflux of organic anions from the liver into the bloodstream (sinusoidal efflux) with specific reference to the influence of albumin. The net sinusoidal efflux rate of dibromosulfophthalein (DBSP) from preloaded livers, being the resultant of sinusoidal efflux and reuptake of ligand by hepatocytes downstream the sinusoid, can be strongly increased by the presence of bovine serum albumin (BSA), a protein having multiple binding sites for DBSP. We previously attributed this effect to a reduction of reuptake through extracellular binding of the organic anion to the protein, rather than to an intrinsic stimulatory effect on the actual membrane transport process from the cells. In the present study we tested this hypothesis using a pharmacokinetic multicompartment liver model. This model resembles the parallel tube model in that the liver is described by several compartments placed in series instead of a single well-stirred compartment and it takes into account rates of dissociation and association in binding to proteins in the sinusoidal space. The model parameters were fitted from the sinusoidal efflux and biliary excretion data from efflux experiments measuring the stimulatory effect of various concentrations of BSA. Equilibrium binding of DBSP to albumin as well as the dissociation rate constant (koff) were determined in vitro with rapid filtration techniques. The experimental data could not be fitted satisfactorily when using the experimentally obtained values of the protein association and dissociation rate constants (kon) and koff. However, they could be simulated accurately assuming 16 times higher values for the association and dissociation rate constant compared to those determined in vitro. Time constants of the perfusate flow, liver (re)uptake, and protein association and dissociation indicate that binding equilibrium does not exist within the sinusoids and that, in particular at low protein concentrations, the net sinusoidal efflux rate is association ratelimited: A large fraction of the ligand effluxed from the cell into the medium is taken up by the hepatocyte before binding to the proteins occurs. Higher kon andoff values predicted by the model might indicate altered DBSPalbumin binding characteristics upon passage through the liver but alternatively can be explained by an intrinsic effect of albumin on the carrier-mediated efflux process. Efflux experiments showed a marked stimulatory effect of the protein on sinusoidal efflux but only a moderate effect on biliary excretion, despite a strong decrease in liver content. These patterns indicate that sinusoidal efflux and biliary excretion occur from two different intraceltular compartments that equilibrate slowly.
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M. H. De Vries, G. M. M. Groothuis, G. J. Mulder, H. Nguyen, and D. K. F. Meijer. Secretion of the organic anion harmol sulfate from the liver into blood. Evidence for a carrier-mediated mechanism.Biochem. Pharmacol. 34:2129–2135 (1985).
D. K. F. Meijer, A. Blom, J. G. Weitering, and R. Hornsveld. Pharmacokinetics of the hepatic transport of organic anions. Influence of extraand intracellular binding on hepatic storage of dibromosulfophthalein and interaction with indocyanine green.J. Pharmacokinet. Biopharm. 12:43–65 (1984).
J. L. Gollan, M. A. O'Donovan, M. C. Carey, and K. D. R. Setchell. Hepatocellular uptake, efflux and sorting of bile salts: studies in isolated perfused liver. In G. Paumgartner, A. Stiehl, and W. Gerok (eds.),Bile Acids and the Liver, MTP, Lancaster, England, 1986, pp. 143–145.
D. J. Sweeny and L. A. Reinke. Metabolism of benzo[a]pyrene in the perfused rat liver: factors affecting the release of phenolic metabolites into the bile and perfusate.Carcinogenesis 8:779–783 (1987).
H. M. J. Nijssen, T. Pijning, D. K. F. Meijer, and G. M. M. Groothuis. Influence of albumin on the net sinusoidal efflux of the organic anion dibromosulfophthalein from rat liver.Hepatology 15:302–309 (1992).
R. A. Weisiger, J. Gollan, and R. Ockner. Receptor for albumin on the liver cell surface may mediate uptake of fatty acids and other albumin-bounds substances.Science 211:1048–1051 (1981).
E. L. Forker and B. A. Luxon. Albumin helps mediate removal of taurocholate by rat liver.J. Clin. Invest. 67:1517–1522 (1981).
E. L. Forker, B. A. Luxon, M. Snell, and W. O. Shurmantine. Effect of albumin on the hepatic transport of rose bengal: surface-mediated dissociation of limited capacity.J. Pharmacol. Exp. Ther. 223:342–347 (1982).
E. L. Forker and B. A. Luxon. Albumin-mediated transport of rose bengal by perfused rat liver. Kinetics of the reaction at the cell surface.J. Clin. Invest. 72:1764–1771 (1983).
R. K. Ockner, R. A. Weisiger, and J. L. Gollan. Hepatic uptake of albumin-bound substances: albumin receptor concept.Am. J. Physiol. 245:G13-G18 (1983).
R. A. Weisiger, C. M. Zacks, N. D. Smith, and J. L. Boyer. Effect of albumin binding on extraction of sulfobromophthalein by perfused elasmobranch liver: evidence for dissociation-limited uptake.Hepatology 4:492–501 (1984).
R. A. Weisiger. Dissociation from albumin: A potentially rate limiting step in the clearance of substances by the liver.Proc. Natl. Acad. Sci. U.S. 82:1563–1567 (1985).
P. Van der Sluijs, B. Postema, and D. K. F. Meijer. Lactosylation of albumin reduces uptake rate of dibromosulfophthalein in perfused rat liver and dissociation rate from albumin in vitro.Hepatology 7:688–695 (1987).
T. Horie, T. Mizuma, S. Kasai, and S. Awazu. Conformational change in plasma albumin due to interaction with isolated rat hepatocyte.Am. J. Physiol. 254:G465-G470 (1988).
R. Nunes, C. L. Kiang, D. Sorrentino, and P. D. Berk. “Albumin-receptor” uptake kinetics do not require an intact lobular architecture and are not specific for albumin.J. Hepatol. 7:293–304 (1988).
M. Inoue, E. Hirata, Y. Morino, S. Nagase, J. Roy Chowdhury, N. Roy Chowdhury, and I. M. Arias. The role of albumin in the hepatic transport of bilirubin: studies in mutant analbuminemic rats.J. Biochem. 97:737–743 (1985).
S. C. Tsao, Y. Sugiyama, K. Shinmura, Y. Sawada, S. Nagase, T. Iga, and M. Hanano. Protein-mediated hepatic uptake of rose bengal in analbuminemic rats (NAR). Albumin is not indispensable to the protein-mediated transport of rose bengal.Drug Metab. Dispos. 16:482–489 (1988).
L. Bass and S. M. Pond. The puzzle of cellular rates of uptake of protein bound ligands. In A. Pecile and A. Resigno (eds.),Pharmacokinetics: Mathematical and Statistical Approaches, Plenum Press, London, 1988, pp. 245–269.
G. M. M. Groothuis, K. P. T. Keulemans, M. J. Hardonk, and D. K. F. Meijer. Acinar heterogeneity in hepatic transport of dibromosulfophthalein and ouabain studied by autoradiography, normal and retrograde perfusions and computer simulation.Biochem. Pharmacol. 32:3069–3078 (1983).
R. Kroker, M. S. Anwer, and D. A. Hegner. A compartmental model for hepatic transport of taurocholic acid in isolated perfused rat liver.Naunyn-Schmiedebergs Arch. Pharmacol. 303:287–293 (1978).
R. A. Weisiger, C. M. Mendel, and R. R. Cavalieri. The hepatic sinusoid is not wellstirred: Estimation of the degree of axial mixing by analysis of lobular concentration gradients formed during uptake of thyroxine by the perfused rat liver.J. Pharm. Sci. 75:233–237 (1986).
M. R. Gray and Y. K. Tarn. The series-compartment model for hepatic elimination.Drug Metab. Dispos. 15:27–31 (1987).
I. Braakman, G. M. M. Groothuis, and D. K. F. Meijer. Zonal compartmentation of perfused rat liver: Plasma reappearance of rhodamine B explained.J. Pharmacol. Exp. Ther. 249:869–873 (1989).
C. A. Goresky, G. G. Bach, A. W. Wolkoff, C. P. Rose, and D. Cousineau. Sequestered tracer outflow recovery in multiple indicator dilution experiments.Hepatology 5:805–814 (1985).
D. L. Gumucio, J. J. Gumucio, J. A. P. Wilson, C. Cutter, M. Krauss, R. Caldwell, and E. Chen. Albumin influences sulfobromophthalein transport by hepatocytes of each acinar zone.Am. J. Physiol. 246:G86-G95 (1984).
A. Svenson, E. Holmer, and L. D. Andersson. A new method for the measurement of dissociation rates for complexes between small ligands and proteins as applied to the palmitate and bilirubin complexes with serum albumin.Biochim. Biophys. Acta 342:54–59 (1974).
M. M. Bradford. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding.Anal. Biochem. 72:248–254 (1976).
D. Sasse. Liver structure and innervation. In R. G. Thurman, F. C. Kaufman, and K. Jungermann (eds.),Regulation of Hepatic Metabolism. Intra- and Intercellular Compartmentation, Plenum Press, New York, 1986, pp. 3–25.
R. J. Vonk, M. Danhof, T. Coenraads, A. B. D. Van Doom, K. Keulemans, A. H. J. Scaf, and D. K. F. Meijer. Influence of bile salts on hepatic transport of dibromosulphthalein.Am. J. Physiol. 237:E524-E534 (1979).
J. A. Neider and R. A. Mead. A simplex method for function minimization.Comput. J. 7:308–313 (1965).
W. H. Press, B. P. Flannery, S. A. Teukolsky, and W. T. Vetterling.Numerical Recipes, Cambridge University Press, New York, 1987, pp. 498–546.
J. M. Thompson. Further studies of binding of bromosulfophthalein sodium by human serum albumin: Effects of albumin concentration and buffer composition.Br. J. Pharmacol. 47:133–137 (1973).
S. M. Pederson. Influence of ionic strength on the binding of sodium aurothiosulphate to human serum albumin.Biochem. Pharmacol. 34:4319–4323 (1985).
R. A. Weisiger and W. L. Ma. Uptake of oleate from albumin solutions by rat liver. Failure to detect catalysis of the dissociation of oleate from albumin by an albumin receptor.J. Clin. Invest. 79:1070–1077 (1987).
R. A. Weisiger, S. Pond, and L. Bass. Hepatic uptake of protein-bound ligands: extended sinusoidal perfusion model.Am. J. Physiol. 261:G872-G884 (1991).
A. Blom, K. Keulemans, and D. K. F. Meijer. Transport of DBSP by isolated rat hepatocytes.Biochem. Pharmacol. 30:1809–1816 (1981).
W. Stremmel, B. J. Potter, and P. D. Berk. Studies of albumin binding to rat liver plasma membranes: implications for the albumin receptor hypothesis.Biochim. Biophys. Acta 756:20–27 (1983).
R. G. Reed and C. M. Burrington. The albumin receptor effect may be due to a surface-induced conformational change in albumin.J. Biol. Chem. 264:9867–9872 (1989).
J. Wilting, B. J. 't Hart, and J. J. de Gier. The role of albumin conformation in the binding of diazepam to human serum albumin.Biochim. Biophys. Acta. 626:291–298 (1980).
J. Wilting, W. F. Van der Giesen, L. H. M. Janssen, M. M. Weideman, M. Otagiri, and J. H. Perrin. The effect of albumin conformation on the binding of warfarin to human serum albumin.J. Biol. Chem. 255:3032–3037 (1980).
E. L. M. Vansterkenburg, J. Wilting, and L. H. M. Janssen. Influence of pH on the binding of suramin to human serum albumin.Biochem. Pharmacol. 38:3029–3035 (1989).
R. A. Weisiger, S. M. Pond, and L. Bass. Albumin enhances unidirectional fluxes of fatty acid across a lipid-water interface: theory and experiments.Am. J. Physiol. 257:G904-G916 (1989).
M. Ichikawa, S. C. Tsao, T. H. Lin, S. Miyauchi, Y. Sawada, T. Iga, M. Hanano, and Y. Sugiyaina. ‘Albumin-mediated transport phenomenon’ observed for ligands with high membrane permeability.J. Hepatol. 16:38–49 (1992).
D. K. F. Meijer, R. J. Vonk, K. Keulemans, and J. G. Weitering. Hepatic uptake and biliary excretion of dibromosulfophthalein, albumin dependence, influence of phenobarbital and nafenopin pretreatment and the role of Y and Z protein.J. Pharmacol. Exp. Ther. 202:8–21 (1977).
B. L. Blitzer and L. Lyons. Enhancement of Na-dependent bile acid uptake by albumin: direct demonstration in rat basolateral plasma membrane vesicles.Am. J. Physiol. 249:G34-G38 (1985).
S. Øie and F. Fiori. Effects of albumin and alpha-l acid glycoprotein on elimination of prazosin and antipyrine in the isolated perfused rat liver.J. Pharmacol. Exp. Ther. 234:636–640 (1985).
J. A. T. P. Meuwissen, B. Ketterer, and K. P. M. Heirwegh. Role of soluble binding proteins in overall hepatic transport of bilirubin. In P. D. Berk and N. I. Berlin (eds.),Chemistry and Physiology of Bile Pigments, Fogarty International Center Proceedings No. 35, National Institute of Health, Bethesda, MD, 1977, pp. 323–337.
E. Tipping and B. Ketterer. The influence of soluble binding proteins on lipophile transport and metabolism in hepatocytes.Biochem. J. 195:441–452 (1981).
R. Burr, M. Schwenk, and E. Pfaff. Interaction of BSP with mitochondrial membranes. Uptake of BSP and effect on ANS-fluorescence.Biochem. Pharmacol. 26:457–460 (1977).
Y. Laperche and P. Oudea. Inhibition by sulfobromophthalein of mitochondrial translocation of anions and adenine nucleotides: effects upon liver adenosine triphosphate and possible correlation with inhibition of bile flow in the rat.J. Pharmacol. Exp. Ther. 197:236–243 (1976).
D. K. F. Meijer, J. G. Weitering, and R. J. Vonk. Hepatic uptake and biliary excretion of d-tubocurarine and trimethyltubocurarine in the rat in vivo and in isolated perfused rat livers.J. Pharmacol. Exp. Ther. 198:229–238 (1976).
F. A. Simion, B. Fleisher, and S. Fleisher. Two distinct mechanisms for uptake in subcellular fractions from rat liver.J. Biol. Chem. 259:10814–10822 (1984).
S. Erlinger. Hepatocytes bile secretion: Current views and controversies.Hepatology 1:352–359 (1981).
J. M. Crawford, C. A. Berken, and J. L. Gollan. Role of the hepatocyte microtubular system in the excretion of bile salts and biliary lipid: implications for intracellular vesicular transport.J. Lipid Res. 29:144–156 (1988).
J. M. Crawford, S. C. Hauser, and J. L. Gollan. Formation, hepatic metabolism and transport of bile pigments.Semin. Liver Dis. 8:105–118 (1988).
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This investigation has been supported by the Foundation for Medical and Health Research MEDIGON (Grant 900-523-064).
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Proost, J.H., Nijssen, H.M.J., Strating, C.B. et al. Pharmacokinetic modeling of the sinusoidal efflux of anionic ligands from the isolated perfused rat liver: The influence of albumin. Journal of Pharmacokinetics and Biopharmaceutics 21, 375–394 (1993). https://doi.org/10.1007/BF01061688
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DOI: https://doi.org/10.1007/BF01061688