GABA-A family of receptors, and they form ligand-gated chloride channels, but insensitivity of the homopentamers to baclofen and bicuculline as well as benzodiazepines lead them to also be classified as GABA-C receptors (Bormann, 2000; Kusama et al., 1993; Shimada et al., 1992; Zhang et al., 2001). GABA-C receptors have a higher sensitivity to GABA and do not desensitize (Enz, 2001). In the superior colliculus they appear to be involved in long-term potentiation (Enz, 2001; Schmidt et al., 2001).
