Abstract
Increased benzodiazepine (BZ) receptor density has been reported in brains of rabbits with hepatic encephalopathy (HE) due to galactosamine (GalN)-induced fulminant hepatic failure (FHF). These data were generated using detergent-Triton X-100-treated neural membranes. While performing further studies it was noted that the increase in BZ receptor density was not demonstrable when Triton X-100 preparation was not employed. Accordingly the binding of [3H] flunitrazepam, a BZ ligand, to neural membranes from cortices of normal rabbits and rabbits with HE due to (GalN)-induced FHF was studied with and without detergent preparation. Scatchard plot analysis of the binding data indicated that when no detergent was employed, the apparent affinity and density of BZ receptors were similar for control membranes and membranes from animals in HE. BZ receptors from animals in HE were shown to be more resistant to solubilization by Triton than control membranes. These findings (a) afford a potential explanation for the apparent increase in density of BZ receptors in this model when Triton treatment of neural membranes is utilized and (b) suggest that recent evidence for increased GABAergic tone in the syndrome of HE is not dependent on an increased density of BZ receptors.
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Bansky, G., Meier, P. J., Ziegler, W. H., Walser, H., Schmid, M., and Huber, M. (1985), Reversal of hepatic coma by a benzodiazepine antagonist (Ro-15-1788).Lancet 1: 1324–1325 (letter).
Bansky, G., Meier, P. J., Reiderer, F., Walser, H., Ziegler, W. H., and Schmid, M. (1987). Effect of a benzodiazepine antagonist in hepatic encephalopathy in man.Hepatology 7: 1003.
Baraldi, M., Zeneroli, M. L., Ventura, E., Penne, A., Pinelli, G., Ricci, P., and Santi, M. (1984). Supersensitivity of benzodiazepine receptors in hepatic encephalopathy due to fulminant hepatic failure in the rat: Reversal by a benzodiazepine antagonist.Clin. Sci. 67: 167–175.
Basile, A. S., and Skolnick, P. (1986). Subcellular localization of “peripheral-type” binding sites for benzodiazepine in rat brain.J. Neurocchem. 46: 305–308.
Basile, A. S., Gammal, S. H., Mullen, K. D., Jones, E. A., and Skolnick, P. (1988). Differential responsiveness of cerebellar purkinje neurons to GABA and benzodiazepine receptor ligands in an animal model of hepatic encephalopathy.J. Neurosci. 8: 2414–2421.
Bassett, M. L., Mullen, K. D., Skolnick, P., and Jones, E. A. (1987). Amelioration of hepatic encephalopathy by pharmacologic antagonism of the GABAA-benzodiazepine receptor complex in a rabbit model of fulminant hepatic failure.Gastroenterology 93: 1069–1077.
Breckenridge, W. C., Breckenridge, J. E., and Morgan, I. E. (1972). Glycoproteins of the synaptic region. In Davidson, A. N., Morgan, I. G., and Mandel, P. (eds.),Structural and Functional Proteins of the Nervious System, Adv. Exp. Med. Biol., 32, Plenum Press, New York, pp. 135–153.
Bruns, R. F., Lawson-Wendling, K., and Pugsley, T. A. (1983). A rapid filtration assay for soluble receptors using polyethylenimine-treated filters.Ann. Biochem. 132: 74–81.
Enna, S. J., and Snyder, S. H. (1975). Properties of GABA receptor binding in rat brain synaptic membrane fractions.Brain. Res. 100: 81–97.
Ferenci, P., Pappas, S. C., Munson, P. J., Hanson, K., and Jones, E. A. (1984). Changes in the status of neurotransmitter receptors in a rabbit model of hepatic encephalopathy.Hepatology 4: 186–191.
Ferenci, P., Grimm, G., Meryn, S., and Gangl, A. (1988). Successful longterm treatment of portal-systemic encephalopathy by the benzodiazepine antagonist Flumazenil.Gastroenterology 96: 240–243.
Gombos, G., Morgan, I. G., Waehneldt, T. V., Vincedon, G., and Breckenridge, W. C. (1972). Glycoproteins of the synaptic plasma membrane. In Zambotti, V., Tettamani, G., and Arrigoni, M. (eds.),Glycolipids, Glycoproteins and Mucopolysaccharides of the Nervous System. Adv. Exp. Med. Biol., 32, Plenum Press, New York, pp. 101–113.
Grimm, G., Ferenci, P., Katzenschlager, R., Madl, C., Schneeweiss, B., Laggner, A. N., Lenz, K., and Gangl, A. (1988). Improvement of hepatic encephalopathy with Flumazenil.Lancet 2: 1392–1394.
Guidotti, A., Toffano, G., and Costa, E. (1978). An endogenous protein modulates the affinity of GABA and benzodiazepine receptors in rat brain.Nature (London) 275: 553–555.
Jones, E. A., and Schafer, D. F. (1986). Hepatic encephalopathy: A neurochemical disorder. In Popper, H., and Schaffner, S. (eds.),Progress in Liver Diseases, Vol. 8, Grune and Stratton, New York, pp. 525–540.
Jones, E. A., Mullen, K. D., and Gammal, S. H. (1987). Hepatic encephalopathy. In Arias, I. M., Frenkel, M., and Wilson, J. H. P. (eds.),The Liver Annual, Vol. 6, Elsevier, Amsterdam, 396–422.
Klotz, U., and Walker, S. (1989). Flumazenil and hepatic encephalopathy.Lancet 1: 155–156 (letter).
Lowry, O. H., Rosenbrough, N. J., Farr, A. L., and Randall, R., J. (1951). Protein measurement with the Folin phenol reagent.J. Biol. Chem. 193: 265–275.
Massotti, M. D., Guidotti, A., and Costa, E. (1981). Characterization of benzodiazepine and gammaaminobutyric acid recognition sites and their endogenous modulators.J. Neurosci. 1: 409–418.
Mullen, K. D., Schafer, D. E., Cuchi, P., Rössle, M., Maynard, T. F., and Jones, E. A. (1988a). Evaluation of the suitability of galactosamine-induced fulminant hepatic failure as a model of hepatic encephalopathy in the rat and the rabbit. In Soeters, P. B., Wilson, J. H. P., Meyer, A. J., and Holm, E. (eds.),Advances in Ammonia Metabolism and Hepatic Encephalopathy, Elsevier, Amsterdam, pp. 205–212.
Mullen, K. D., Martin, J. V., Mendelson, W. B., Bassett, M. L., and Jones, E. A. (1988b). Could an endogenous benzodiazepine ligand contribute to hepatic encephalopathy?Lancet 1: 457–459.
Munson, P. J., and Rodbard, D. (1980). LIGAND: A versatile computerized approach for characterization of ligand binding systems.Ann. Biochem. 1070: 220–229.
Newby, A. C. (1984). The solubilization of membrane proteins. In Marangos, P. J., Campbell, I. C., and Cohen, R. M. (eds.),Brain Receptor Methodologies, Part A, Academic Press, New York, pp. 76–92.
Olsen, R. W. (1984). Solubilized BABA receptors. In Barkers, J. L., and McKelvy, J. F. (eds.),Current Methods in Cellular Neurobiology, Vol. 2, Wiley, New York, pp. 247–264.
Pappas, S. C., Ferenci, P., and Jones, E. A. (1984). Hepatic encephalopathy: A disorder of synaptic membrane composition and fluidity? In Kleinberger, G., Ferenci, P., Riederer, P., and Thaler, H. (eds.),Advances in Hepatic Encephalopathy and Urea Cycle Disease, Karger, Basel, pp. 331–336.
Rössle, M., and Deckert, J. (1988). Quantitative autoradiography of gamma-aminobutryric acid and benzodiazepine receptors in a model of acute hepatic encephalopathy. In Soeters, P. B., Wilson, J. H. P., Meyer, A. J., and Holm, E. (eds.),Advances in Ammonia Metabolism and Hepatic Encephalopathy, Elsevier, Amsterdam, pp. 233–237.
Rössle, M., Mullen, K. D., Jones, D. B., and Jones, E. A. (1986). Hepatic encephalopathy: A disorder of neural membrane glycosylation?Gastroenterology 90: 1762.
Schafer, D. F. (1987). Hepatic coma, studies on the target organ.Gastroenterology 93: 1132–1134.
Schafer, D. F., Fowler, J. M., Munson, P. J., Thakur, A. K., Waggoner, J. G., and Jones, E. A. (1983). Gamma-amino-butyric acid and benzodiazepine receptors in an animal model of fulminant hepatic failure.J. Lab. Clin. Med. 102: 870–880.
Schafer, D. F., Pappas, S. C., Brody, L. E., Jacobs, R., and Jones, E. A. (1984). Visual evoked potentials in a rabbit model of hepatic encephalopathy.Gastroenterology 86: 540–545.
Scharschmidt, B. F., Keefe, E. B., Blamkenship, N. M., and Ockner, R. K. (1979). Validation of a recording spectrophotometric method for the measurement of membrane associated Mg- and Na, K-ATP-ase activity.J. Lab. Clin. Med. 93: 790–799.
Scollo-Lavizzari, G., and Steinmann, E. (1985). Reversal of hepatic coma by a benzodiazepine antagonist (Ro-15-1788).Lancet 1: 1324 (letter).
Siegal, S. (1956). The Mann-Whitney U test. InNonparametric Statistics for the Behavioral Sciences, McGraw-Hill, New York, pp. 116–127.
Squires, R. F. (1982). Benzodiazepine receptors. In Lajtha, A. (ed.),Handbook of Neurochemistry, Vol. 6, Plenum Press, New York, pp. 261–305.
Sutherland, L. R., and Minuk, G. Y. (1988). Ro 15-1788 and hepatic failure.Ann. Intern. Med. 108: 158 (letter).
Sweetnam, P. M., and Tallman, J. F. (1986). Regional difference in brain benzodiazepine receptor carbohydrates.Mol. Pharmocol. 29: 299–306.
Zieve, L., Ferenci, P., Rzepczynski, D., Ebner, J., and Zimmerman, C. H. (1987). A benzodiazepine antagonist does not alter the course of hepatic encephalopathy or neural γ-aminobutryric acid (GABA) binding.Metab. Brain Dis. 2: 201–205.
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Rössle, M., Mullen, K.D. & Jones, E.A. Cortical benzodiazepine receptor binding in a rabbit model of hepatic encephalopathy: The effect of Triton X-100 on receptor solubilization. Metab Brain Dis 4, 203–212 (1989). https://doi.org/10.1007/BF01000296
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DOI: https://doi.org/10.1007/BF01000296