Gabazine
Chemical compound
Gabazine (SR-95531 ) is a drug that acts as an antagonist at GABAA receptors . It is used in scientific research and has no role in medicine, as it would be expected to produce convulsions if used in humans.[ 1]
Gabazine binds to the GABA recognition site of the receptor-channel complex and acts as an allosteric inhibitor of channel opening.[ 2] The net effect is to reduce GABA-mediated synaptic inhibition by inhibiting chloride flux across the cell membrane, and thus inhibiting neuronal hyperpolarization. While phasic (synaptic) inhibition is gabazine-sensitive, tonic (extrasynaptic) inhibition is relatively gabazine-insensitive.[ 3]
Gabazine has been found to bind to and antagonize α4 βδ subunit -containing GABAA receptors, which may represent the GHB receptor .[ 4]
References
^ Behrens CJ, van den Boom LP, Heinemann U (April 2007). "Effects of the GABA(A) receptor antagonists bicuculline and gabazine on stimulus-induced sharp wave-ripple complexes in adult rat hippocampus in vitro". The European Journal of Neuroscience . 25 (7): 2170–2181. doi :10.1111/j.1460-9568.2007.05462.x . PMID 17419756 . S2CID 85328190 .
^ Ueno S, Bracamontes J, Zorumski C, Weiss DS, Steinbach JH (January 1997). "Bicuculline and gabazine are allosteric inhibitors of channel opening of the GABAA receptor" . The Journal of Neuroscience . 17 (2): 625–634. doi :10.1523/jneurosci.17-02-00625.1997 . PMC 6573228 . PMID 8987785 .
^ Yeung JY, Canning KJ, Zhu G, Pennefather P, MacDonald JF, Orser BA (January 2003). "Tonically activated GABAA receptors in hippocampal neurons are high-affinity, low-conductance sensors for extracellular GABA". Molecular Pharmacology . 63 (1): 2–8. doi :10.1124/mol.63.1.2 . PMID 12488530 . S2CID 6827514 .
^ Absalom N, Eghorn LF, Villumsen IS, Karim N, Bay T, Olsen JV, et al. (August 2012). "α4βδ GABA(A) receptors are high-affinity targets for γ-hydroxybutyric acid (GHB)" . Proceedings of the National Academy of Sciences of the United States of America . 109 (33): 13404–13409. Bibcode :2012PNAS..10913404A . doi :10.1073/pnas.1204376109 . PMC 3421209 . PMID 22753476 .
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