GABA receptors binding sites

In addition to presynaptic receptors, autoradiographic studies have indicated the presence of postsynaptic H3-receptor binding sites as well. Chemical destruction of postsynaptic structures in the striatum using quinolinic and kainic acid resulted in a marked decrease of striatal H3-receptor binding sites (Cumming et al., 1991 Pollard et al., 1993 Ryu et al., 1994). Consequently, a major part of the striatal H3-receptors may be located on striatal GABA neurons, representing more than 85% of the striatal efferents (Kita Kitai, 1988). 

Padgett, C. L., Hanek, A. P., Lester, H. A., et al. (2007) Unnatural amino acid mutagenesis of the GABA(A) receptor binding site residues reveals a novel cation-pi interaction between GABA and beta(2)Tyr97. Journal of Neuroscience, 27(4), 886-892. 

Kril, J. J., Dodd, P. R., and Gundlach, A. L. 1988. Necropsy study of GABA/benzodiaz-epine receptor binding sites in brain tissue from chronic alcoholic patients. Clin. Exp. Neurol. 25 135-41. 

Fig. 15. Drug binding sites associated with the GABA receptor—channel complex where (— -) represents the carbon backbone of GABA agonists.

Synaptic vesicles mediate the release of small molecules other than classical neurotransmitters and neuropeptides. Of these, zinc and ATP are the best characterized. NMDA and GABA receptors contain binding sites for zinc, and zinc exerts a direct effect on... 

Atack JR Anxioselective compounds acting at the GABA(A) receptor benzodiazepine binding site. Curr Drug Target CNS Neurol Disord 2 213—232, 2003... 

In one example (Lawrence and Casida 1984, Abalis et al. 1985) rat brain microsacs were used to test the action of cyclodiene insecticides such as dieldrin and endrin on the GABA receptors contained therein. The influx of radiolabeled CL into the microsacs via the pore channel of the receptor was inhibited by these chemicals. A similar assay was developed using microsacs from cockroach nerve. Assays with this preparation showed again the inhibitory effect of a cyclodiene (this time heptachlor epoxide) on CL influx. Also, that microsacs from cyclodiene resistant cockroaches were insensitive to the inhibitory effect of picrotoxinin, which binds to the same site on the GABA receptor (Kadous et al. 1983). 

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