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Erratum: Chén “The Roles of Statistics in Human Neuroscience”, Brain Sci. 2019, 9, 194
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Flumazenil-Insensitive Benzodiazepine Effects in Recombinant αβ and Neuronal GABAA Receptors

State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Key Laboratory of Neuropsychopharmacology, Beijing Institute of Pharmacology and Toxicology, 27th Taiping Road, Beijing 100850, China
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Brain Sci. 2020, 10(3), 150; https://doi.org/10.3390/brainsci10030150
Received: 10 February 2020 / Revised: 28 February 2020 / Accepted: 2 March 2020 / Published: 5 March 2020
Gamma-aminobutyric acid, type A (GABAA) receptors are complex heterogeneous pentamers with various drug binding sites. Several lines of evidence suggest that benzodiazepines modulate certain GABAA receptors in a flumazenil-insensitive manner, possibly via binding sites other than the classical ones. However, GABAA receptor subtypes that contain non-classical benzodiazepine binding sites are not systemically studied. The present study investigated the high-concentration effects of three benzodiazepines and their sensitivity to flumazenil on different recombinant (α1β2, α2β2, α3β2, α4β2, α5β2 and α1β3) and native neuronal GABAA receptors using the whole-cell patch-clamp electrophysiology technique. The classical benzodiazepine diazepam (200 μmol/L) and midazolam (200 μmol/L) produced flumazenil-insensitive effects on α1β2 receptor, whereas the imidazopyridine zolpidem failed to modulate the receptor. Flumazenil-insensitive effects of diazepam were also observed on the α2β2, α3β2 and α5β2, but not α4β2 receptors. Unlike β2-containing receptors, the α1β3 receptor was insensitive to diazepam. Moreover, the diazepam (200 μmol/L) effects on some cortical neurons could not be fully antagonized by flumazenil (200 μmol/L). These findings suggested that the non-classical (flumazenil-insensitive) benzodiazepine effects depended on certain receptor subtypes and benzodiazepine structures and may be important for designing of subtype- or binding site- specific drugs. View Full-Text
Keywords: diazepam; benzodiazepine; GABAA receptors; αβ receptors; benzodiazepine binding sites diazepam; benzodiazepine; GABAA receptors; αβ receptors; benzodiazepine binding sites
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Lian, J.-J.; Cao, Y.-Q.; Li, Y.-L.; Yu, G.; Su, R.-B. Flumazenil-Insensitive Benzodiazepine Effects in Recombinant αβ and Neuronal GABAA Receptors. Brain Sci. 2020, 10, 150.

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