GABA receptors subtypes

Sanna E, Busonero F, Talani G, et al Comparison of the effects of zaleplom, zolpidem, and triazolam at various GABA, receptor subtypes. Eur J Pharmacol 431 103— 110, 2002... 

A second GABA receptor subtype, the GABA-B receptor (Fig. 8—12) is not allo-sterically modulated by benzodiazepines but binds selectively to the muscle relaxant baclofen. Its physiological role is not well known yet, but does not appear to be closely linked to anxiety disorders or to anxiolytics. 

The issue of dimerization of type C (glutamate receptor class) is clearly set. Type C GPCRs form dimers by covalent linkage of disulfide bond at their extracellular N-terminal domains (e.g. metabotropic glutamate receptor) or by strong non-covalent, intermolecular interactions (e.g. two y-aminobutyric acid, GABA, receptor subtypes). But is dimerization state also required for their function ... 

The cited reviews pertaining to GABA/ben-zodiazepine receptors discuss numerous other studies that employ chimeric receptors and site-directed mutagenesis to determine the key structural components of GABA receptor subtypes comprised of various a, j8, and 7 subunit permutations. 

GABA Receptor Subtype Linked Activated Modulated Response to Bicuculline... 

Along with an increased understanding of the molecular diversity and anatomical localization of different GABA receptor subtypes has come the notion that specific clinical effects may reside in specific subtypes. The selective affinity of the hypnotic agent zolpidem... 

Benke D, Mertens S, Trzeciak A, Gillessen D, Mohler H (1991b) Identification and immunohistochemical mapping of GABA. receptor subtypes containing the <5-subunit in rat brain. FEBS, 283, 145-149. 

Rudolph, U., Crestani, F., Benke, D., Martin, J.R., Benson, J.A., Keist, R., Fritschy, J.M., Low, K., Bluthmann, H.. Mohler, H., 1998. Function of GABA -receptor subtypes mice with point-mutated diazepam insensitive a,-subunits. Soc. Neurosci. Abstr. 24, 1990, cited in Rudolph and Mohler (1999). 

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