Pharmacological modulation of anxiety-related behaviors in the murine Suok test

We have recently introduced a new model of anxiety - the Suok test and its light-dark modification - for behavioral characterization in mice and rats, including simultaneous assessment of their anxiety, activity, and neurological phenotypes. In the present study, testing different inbred (129S1, BALB/c) and hybrid (C57-129S1) mouse strains in both Suok test modifications, we examined the effects on anxiety-related behaviours produced by traditional anxiogenic and anxiolytic drugs. Here we show dose-dependent increases in anxiety-related behaviors produced by anxiogenic drug pentylenetetrazole (10 and 20 mg/kg). In contrast, anxiolytic drugs ethanol (0.75 and 1.5 g/kg) and diazepam (0.5 mg/kg) reduced anxiety and increased mouse exploration in this test. Hyperemotional anxious BALB/c mice were particularly sensitive to pharmacogenic anxiety in Suok test, also showing robust light-dark shifts in the light-dark version of this test. Overall, the results of this study confirm the potential utility of both murine Suok tests, especially when used in selected "sensitive" mouse strains, for high-throughput screening of potential anxiotropic drugs.