ZK93423 is a potent agonist of benzodiazepine receptor (IC50 = 1 nM) with non-selective between α1-, α2-, α3- and α5-subunit containing GABAA receptors, Ki values are 4.1, 4.2, 6 and 4.5 nM for inhibition of [3H]Ro15-1788 binding to human recombinant α1β3