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The Effect of Anticonvulsant Drugs on GABA-Stimulated Chloride Uptake

Published online by Cambridge University Press:  18 September 2015

J. Francis
Affiliation:
Department of Pharmacology, University of Toronto, Toronto Bloorview Epilepsy Program, University of Toronto, Toronto
S.J. Mihic
Affiliation:
Department of Pharmacology, University of Toronto, Toronto
W.B. Sneddon
Affiliation:
Department of Pharmacology, University of Toronto, Toronto
W.M. Burnham*
Affiliation:
Department of Pharmacology, University of Toronto, Toronto Bloorview Epilepsy Program, University of Toronto, Toronto
*
Department of Pharmacology, Medical Sciences Building, University of Toronto, Toronto, Ontario, Canada M5S 1A8
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Abstract:

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Eight anticonvulsant drugs – including clonazepam, diazepam and phenobarbital – were tested for their effects on GABA-stimulated chloride uptake in rat cerebral cortical microsacs (unfiltered synaptoneurosomes). “Mid” and “high” therapeutic concentrations were screened, and, if significant enhancement was found, full concentration-response tests were done. In the initial screens, enhancement of GABA-stimulated uptake was found only with phenobarbital, clonazepam and diazepam. In subsequent concentration-response tests, the effects of phenobarbital were found to occur throughout the range of normal, anticonvulsant concentrations, whereas the effects of clonazepam and diazepam were observed only above the concentrations normally used for the chronic control of seizures or anxiety. These data suggest that phenobarbital's anticonvulsant effects are mediated via the GABAA receptor complex, but that the low-dose effects of the benzodiazepines may be mediated via some other mechanism.

Type
Articles
Copyright
Copyright © Canadian Neurological Sciences Federation 1994

References

REFERENCES

1.Iversen, LL and Bloom, FE. Studies of the uptake of 3H-GABA and 3H-glycine in slices and homogenates of rat brain and spinal cord by electron microscopic autoradiography, Brain Res 1972; 41: 131143.CrossRefGoogle Scholar
2.Stephenson, FA. Understanding the GABA-A receptor: a chemically gated ion channel. J Biochem 1988; 249: 2132.CrossRefGoogle ScholarPubMed
3.Olsen, RW. GABA benzodiazepine barbiturate receptor interactions. J Neurochem 1981; 37: 113.CrossRefGoogle ScholarPubMed
4.Barker, JL and McBurney, RW. Phenobarbitone modulation of postsynaptic GABA receptor function on cultured mammalian neurons. Proc R Soc Lond 1979; 206: 319327.Google ScholarPubMed
5.Study, RE and Barker, JL. Diazepam and (-)-pentobarbital: fluctuation analysis reveals different mechanisms for potentiation of GABA responses in cultured central neurons. Proc Nat Acad Sci USA 1981; 78: 71807184.CrossRefGoogle ScholarPubMed
6.Schwartz, RD, Skolnick, P, Seale, TW and Paul, SM. Demonstration of GABA/barbiturate receptor-mediated chloride transport in rat brain synaptoneurosomes: a functional assay of receptor-effector coupling. In: Biggio, G. and Costa, E., eds. Advances in Biochemical Pharmacology. New York: Raven Press 1986; 3349.Google Scholar
7.Tunnicliff, G, Smith, JA and Ngo, TT. Competition for diazepam receptor binding by diphenylhydantoin and its enhancement by gamma-aminobutyric acid. Biochem Biophys Res Commun 1979; 91: 10181024.CrossRefGoogle ScholarPubMed
8.Tallman, JF and Gallagher, DW. The GABAergic system: a locus of benzodiazepine action. Ann Rev Neurosci 1985; 8: 2144.CrossRefGoogle ScholarPubMed
9.Ayala, GF, Lin, S and Johnston, D. The mechanism of action of diphenylhydantoin on invertebrate neurons. I. Effects on basic membrane properties. Brain Res 1977; 121: 245258.CrossRefGoogle ScholarPubMed
10.Aickin, CC, Deisz, RA and Lux, HD. On the action of the anticonvulsant 5,5 diphenylhydantoin and the convulsant picrotoxin in crayfish stretch receptor. J Physiol 1981; 315: 157173.CrossRefGoogle ScholarPubMed
11.Spero, L. Neurotransmitters and CNS disease. Epilepsy. Lancet 1982; 2: 13191322.CrossRefGoogle Scholar
12.Skerritt, JH, Johnston, GA and Chen Chow, S. Interactions of carbamazepine with benzodiazepine receptors. J Pharm Pharmacol 1983; 35: 464465.Google ScholarPubMed
13.Macdonald, RL and Bergey, GK. Valproic acid augments GABA mediated postsynaptic inhibition in cultured mammalian neurons. Brain Res 1979; 170: 558562.Google ScholarPubMed
14.Baldino, F and Geller, HM. Sodium valproate enhancement of inhibition: electrophysiological evidence for anticonvulsant activity. J Pharm ExpTher 1981; 217: 445450.Google ScholarPubMed
15.Loscher, W. Effect of inhibitors of GABA aminotransferase on the metabolism of GABA in brain tissue and synaptosomal fractions. J Neurochem 1981; 36: 15211527.Google Scholar
16.Rock, DM, McLean, MJ and MacDonald, RL. Sodium valproate selectively limits sustained high frequency repetitive firing of cultured mouse neurons. Soc Neurosci Abst 1984; 10: 872.Google Scholar
17.Macdonald, RL and McLean, MJ. Anticonvulsant drugs: mechanisms of action. Adv Neurol 1986; 44: 713736.Google ScholarPubMed
18.Rogawski, MA and Porter, RJ. Antiepileptic drugs: pharmacological mechanisms and clinical efficacy with consideration of promising developmental stage compounds. Pharm Rev 1990; 42: 223286.Google ScholarPubMed
19.Rail, TW and Schleifer, LS. Drugs effective in the therapy of the epilepsies. In: Gilman, A.G.Goodman, L.S.Rail, T.W. and Murad, F. eds. The Pharmacological Basis of Therapeutics. New York: MacMillan Publishing Company 1985; 446472.Google Scholar
20.Krall, RL, Penry, JK, White, BG, Kupferberg, HJ and Swinyard, EA. Antiepileptic drug development II: anticonvulsant drug screening. Epilepsia 1978; 19: 409428.CrossRefGoogle ScholarPubMed
21.Booker, HE and Celesia, GG. Serum concentrations of diazepam in subjects with epilepsy. Arch Neurol 1973; 29: 191194.CrossRefGoogle ScholarPubMed
22.Carien, PL, Gurevich, N, Davies, MF, Blaxter, TJ and O’Beime, MO. Enhanced neuronal K+ conductance: a possible common mechanism for sedative-hypnotic drug action. Can J Physiol Pharmacol 1985; 63: 831837.Google Scholar
23.Carien, PL, Gurevich, N and Pole, P. Low-dose benzodiazepine neuronal inhibition: enhanced Ca2+-mediated K+-conductance. Brain Res 1983; 271: 358364.Google Scholar
24.Harris, RA and Allan, AM. Functional coupling of gamma-aminobu-tyric acid receptors to chloride channels in brain membranes. Science 1985; 228: 11081109.Google ScholarPubMed
25.Schwartz, RD, Jackson, JA, Weigert, D, Skolnick, P and Paul, SM. Characterization of barbiturate-stimulated chloride efflux from rat brain synaptoneurosomes. J Neurosci 1985; 5: 29632970.CrossRefGoogle ScholarPubMed
26.Daly, JW, McNeal, E, Partington, C, Newirth, M and Creveling, CR. Accumulations of cyclic AMP in adenine-labelled cell-free preparations from guinea-pig cerebral cortex: role of alpha-adrenergic and Hl-histaminergic receptors. J Neurochem 1980; 35: 326337.CrossRefGoogle Scholar
27.Hollingsworth, EB, Creveling, CR, McNeal, ET and Daly, JW. A filtered neurosome enriched preparation from brain: morphology, receptors, enzymes, and cyclic AMP responses. Fed Proc 1984; 43: 1093.Google Scholar
28.Hollingsworth, EB, McNeal, ET, Burton, JL, Williams, RJ, Daly, JW and Creveling, CR. Biochemical characterization of a filtered synaptoneurosome preparation from guinea pig cerebral cortex: cyclic adenosine 3’:5’-monophosphate-generating systems, receptors, and enzymes. J Neurosci 1985; 5: 22402253.Google ScholarPubMed
29.Facklam, M, Schoch, P and Haefely, WE. Relationship between benzodiazepine receptor occupancy and potentiation of γ-aminobu-tyric acid-stimulated chloride flux in vitro of four ligands of differing intrinsic efficacies. J Pharmacol Exp Ther 1992; 261: 11061112.Google ScholarPubMed
30.Mihic, SJ, Kalant, H, Liu, JF and Wu, PH. γ-Aminobutyric acid receptor/chloride channel complex in tolerance to ethanol and cross-tolerance to diazepam and pentobarbital. J Pharmacol Exp Ther 1992; 261: 108113.Google ScholarPubMed
31.Mihic, SJ, Wu, PH and Kalant, H. Potentiation of γ-aminobutyricacid-mediated chloride flux by pentobarbital and diazepam but not ethanol. J Neurochem 1992; 58: 745751.CrossRefGoogle Scholar
32.Lowry, OH, Rosebrough, NJ, Farr, AL and Randall, RJ. Protein measurement with the Folin phenol reagent. J Biol Chem 1951; 193: 161175.CrossRefGoogle ScholarPubMed
33.Schwartz, RD, Skolnick, P, Hollingsworth, EB and Paul, SM. Barbiturate and picrotoxin-sensitive chloride efflux in rat cerebral cortical synaptoneurosomes. FEBS Lett 1984; 175: 193196.CrossRefGoogle ScholarPubMed
34.Allan, AM, Gallaher, EJ, Gionet, SE and Harris, RA. Genetic selection for benzodiazepine ataxia produces functional changes in the γ-aminobutyric acid receptor chloride channel complex. Brain Res 1988; 452: 118126.CrossRefGoogle ScholarPubMed
35.Yakushiji, T, Oyama, Y and Akaike, N. Comparative study on barbiturates using single isolated neurons: GABA-mimetic action and augmentatory action on GABA response. Brain Res 1989; 488: 357360.CrossRefGoogle ScholarPubMed
36.Macdonald, RL and McLean, MJ. Cellular bases of barbiturate and phenytoin anticonvulsant drug action. Epilepsia 1982; 23 (Suppl. 1): S7–S18.CrossRefGoogle ScholarPubMed
37.Gilman, AG, Goodman, LS, Rail, TW and Murad, F, eds. The Pharmacological Basis of Therapeutics, 7th edn., New York: MacMillan Publishing Company 1985; 16801683.Google Scholar
38.Obata, T and Yamamura, HI. The effect of benzodiazepines and beta-carbolines on GABA-stimulated chloride influx by membrane vesicles from the rat cerebral cortes. Biochem Biophys Res Commun 1986; 141: 16.Google Scholar
39.Morrow, AL and Paul, SM. Benzodiazepine enhancement of γ-aminobutyric acid-mediated chloride influx in rat brain synaptoneurosomes. J Neurochem 1988; 50: 302306.CrossRefGoogle Scholar
40.Mehta, AK and Ticku, MK. Benzodiazepine and beta-carboline interactions with GABAA receptor-gated chloride channels in mammalian cultured spinal cord neurons. J Pharmacol Exp Ther 1989; 249: 418423.Google ScholarPubMed
41.Skerritt, JH and Macdonald, RL. Benzodiazepine receptor ligand actions on GABA responses: benzodiazepines, CL 218872, Zopiclone. Eur J Pharmacol 1984; 101: 127134.CrossRefGoogle ScholarPubMed
42.White, WF, Dichter, MA and Snodgrass, SR. Benzodiazepine binding and interactions with the GABA receptor complex in living cultures of rat cerebral cortex. Brain Res 1981; 215: 162176.Google ScholarPubMed
43.Skerritt, JH and Johnston, GAR. Enhancement of GABA binding by benzodiazepines and related anxiolytics. Eur J Pharmacol 1983; 89: 193198.CrossRefGoogle ScholarPubMed
44.Baldessarini, RJ. Drugs and the treatment of psychiatric disorders. In: Gilman, AG, Goodman, LS, Rail, TW and Murad, F, eds. The Pharmacological Basis of Therapeutics. New York: Macmillan Publishing Company 1985; 387445.Google Scholar
45.Olsen, RW and Tobin, AJ. Molecular biology of GABAA receptors. FASEB J 1990; 4: 14691480.CrossRefGoogle ScholarPubMed