GABA receptors structure

Gamma aminobutyric acid (GABA) receptors are located on the postsynaptic membranes of inhibitory synapses of both vertebrates and insects and contain within their membrane-spanning structure a chloride ion channel. They are found in both vertebrate brains and invertebrate cerebral ganglia (sometimes referred to as brains) as well as in insect muscles. Particular attention has been given to one form of this receptor—the GABA-A receptor—as a target for novel insecticides (Eldefrawi and Eldefrawi 1990). It is found both in insect muscle and vertebrate brain. The remainder of this description will be restricted to this form. 

Brooks, G.T. (1992). Progress in structure-activity smdies on cage convnlsants and related GABA receptor chloride ionophore antagonists. In D. Otto and B. Weber (Eds.) Insecticides Mechanism of Action and Resistance. Newcastle npon Tyne, UK Intercept Press, 237-242. 

Egebjerg, Schousboe, and Krogsgaard-Larsen, Eds., Glutamate and GABA Receptors and Transporters Structure, Function and Pharmacology, Taylor Francis, London, 2001. 

Cromer, B. A., Morton, C. J., and Parker, M. W. (2002) Anxiety over GABA(A) receptor structure relieved by AChBP. Trends Biochem. Sci. 27,280-287. 

Chang Y, Weiss DS. 2002. Site-specific fluorescence reveals distinct structural changes with GABA receptor activation and antagonism. Nat Neurosci 5 (11) 1163. 

Barnard EA. The molecular biology of GABA receptors and their structural determinants. In Biggio C, Sanna E, and Costa E (eds.). GABAa Receptors and Anxiety From Neurobiology to Treatment. 

Less is known about GABAg receptor structure. GABAg receptors are coupled indirectly to K+ channels. These receptors, which are always inhibitory, are coupled to G-proteins. When activated, GABAg receptors decrease Ca + conductance and inhibit cAMP production. The GABA, receptor is probably little more than a subtype of the GABA receptor. It contains the p subunit peptide and is located primarily, if not exclusively, in the retina. 

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