@article{
author = "Batinić, Bojan and Stanković, Tamara and Stephen, Michael and Kodali, Revathi and Tiruveedhula, Veera V. and Li, Guanguan and Scholze, Petra and Marković, Bojan and Obradović, Aleksandar and Ernst, Margot and Cook, James M. and Savić, Miroslav",
year = "2018",
abstract = "It is unclear whether GABA(A) receptors (GABA(A)Rs) that contain the alpha 3-subunit are substantially involved in the anxiolytic effects of benzodiazepines (BDZs). In the present study, we tested YT-III-31, a newer BDZ ligand with functional preference for alpha 3 ss gamma 2 GABA(A) Rs, in two paradigms of unconditioned anxiety, the open field and elevated plus maze in rats. The effective dose of YT-III-31 (2 mg/kg) displayed a clear anxiolytic-like profile, unhampered by sedative action, in both tests. At a higher dose (10 mg/kg), YT-III-31 induced ataxia in the rotarod and sedation in spontaneous locomotor activity test. The latter effect was preventable by flumazenil and ss CCt, the non-selective and alpha 1 ss gamma 2 GABA(A)R affinity-selective antagonist, respectively, demonstrating that sedative properties of YT-III-31, when attained, are mediated by the alpha 1 gamma 2 site. To elucidate the receptor substrate of subtle behavioral differences between YT-III-31 and diazepam, we approximated in vivo receptor potentiation for both ligands, based on estimated unbound concentrations in rat brains. Far different from diazepam, YT-III-31 has significantly lower affinity for the alpha 1 gamma 2 over other BDZ-sensitive sites, and at lower doses (1-2 mg/kg) was devoid of potentiation at alpha 1 ss gamma 2 GABA(A)Rs. The approximation approach revealed a modest selectivity of YT-III-31 for alpha 3 gamma 2- in comparison to alpha 2 gamma 2 and alpha 5 gamma 2 binding sites, suggesting that its anxiolytic-like activity may not necessarily or predominantly reflect potentiation at alpha 3 ss gamma 2 GABA(A)Rs. Nonetheless, as the anxiolytic effects are achievable at a dose devoid of any sedative potential, and having favorable safety (cytotoxicity) and metabolic stability profile, YT-III-31 represents a valuable candidate for further translational research.",
publisher = "Elsevier Science BV, Amsterdam",
journal = "European Neuropsychopharmacology",
title = "Attaining in vivo selectivity of positive modulation of alpha 3 ss gamma 2 GABA(A) receptors in rats: A hard task!",
volume = "28",
number = "8",
pages = "903-914",
doi = "10.1016/j.euroneuro.2018.05.014"
}
