GABAA receptors (GABAARs) are a class of physiologically and therapeutically important ligand-gated ion channels. These pentameric receptors occur ubiquitously in the brain with diverse subunit composition, which confers highly complex pharmacology to this receptor class. An impressive range of clinically used therapeutics such as anxiolytics, anaesthetics, sedative hypnotics and anticonvulsants are known to bind to distinct sites found on GABAARs to modulate receptor function. Numerous experimental approaches have been used over the years to elucidate the binding sites of these drugs, but unequivocal identification is challenging due to subtype- and ligand-dependent pharmacology. This thesis focuses on two compounds with anxiolytic effects (2′-methoxy-6-methylflavone and kavain) which are believed to be mediated via GABAARs. However, as the subunit requirement for their actions at GABAARs is poorly understood, we sought to investigate this using electrophysiological and mutational approaches on various human recombinant GABAAR subtypes expressed in Xenopus oocytes
