GABAA-positive modulator selective discriminative stimulus effects of 1,1,1-trichloroethane vapor

The results suggest that the discriminative stimulus effects of TCE are fairly selectively mediated by positive modulation of GABAA receptors. The failure of gaboxadol to substitute and the poor substitution by zaleplon suggests that extrasynaptic GABAA receptors as well as GABAA receptors containing alpha1 subunits and are not involved in transducing the discriminative stimulus of TCE. Studies with additional GABAA benzodiazepine-site positive modulators will be necessary to confirm and extend these findings.