Fig. 4.
Tactile/oral exploration and observable ataxia were altered following intravenous injections with selective compounds. Zolpidem has preferential affinity for α1 subunit-containing GABAA receptors, whereas the three compounds have the following profiles: HZ-166 (selective efficacy for α2 and α3 subunit-containing GABAA receptors, full efficacy allosteric modulator), MRK-696 (nonselective partial allosteric modulator), TPA-023B (selective efficacy for α2, α3, and α5 subunit-containing GABAA receptors, partial allosteric modulator). Other details as in Fig. 3. Top panels: Tactile/oral exploration was dose-dependently enhanced and attenuated by zolpidem (note different scaling on y-axis), but attenuated by all other compounds at the highest dose tested; Bottom panels: Observable ataxia was induced by zolpidem and MRK-696 only. Note that *P ≤ 0.05, vs. vehicle (V), Bonferroni t tests, n = 4.