Etifoxine-¹³C-d₃

Etifoxine-¹³C-d₃ is intended for use as an internal standard for the quantification of etifoxine (Item No. 15999) by GC- or LC-MS. Etifoxine is a positive allosteric modulator of α₁β₂γ₂ and α₁β₃γ₂ subunit-containing GABA_A receptors.¹ It selectively increases GABA-induced currents in X. laevis oocytes expressing α₁β₂γ₂ or α₁β₃γ₂ over α₁β₁γ₂ subunit-containing receptors at 20 µM. Etifoxine inhibits binding of the GABA_A receptor agonist muscimol in rat corticol membranes with a K_d value of 23 nM in a radioligand binding assay.² It increases NGF-induced neurite outgrowth in PC12 cells when used at a concentration of 20 µM.³ Etifoxine (12.5 mg/kg, i.p.) increases the percentage of time spent in the open arms of the elevated plus maze in high-anxiety BALB/cByJ, but not C57BL/6, mice, indicating anxiolytic-like activity.⁴ It increases the seizure threshold in a mouse model of seizures induced by picrotoxin (Item No. 20771) with a minimum effective dose (MED) of 75 mg/kg.² Etifoxine (50 mg/kg, i.p.) also increases the paw withdrawal threshold on the ipsilateral side in a rat model of rheumatoid arthritis induced by complete Freund's adjuvant.⁵

WARNING This product is not for human or veterinary use.

1. Hamon, A., Morel, A., Hue, B., et al. The modulatory effects of the anxiolytic etifoxine on GABA_A receptors are mediated by the β subunit. Neuropharmacology 45(3), 293-303 (2003).

2. Verleye, M., Pansart, Y., and Gillardin, J. Effects of etifoxine on ligand binding to GABA_A receptors in rodents. Neurosci. Res. 44(2), 167-172 (2002).

3. Girard, C., Liu, S., Cadepond, F., et al. Etifoxine improves peripheral nerve regeneration and functional recovery. Proc. Natl. Acad. Sci. USA 105(51), 20505-20510 (2008).

4. Verleye, M., Dumas, S., Heulard, I., et al. Differential effects of etifoxine on anxiety-like behaviour and convulsions in BALB/cByJ and C57BL/6J mice: Any relation to overexpression of central GABA_A receptor beta2 subunits? Eur. Neuropsychopharmacol. 21(6), 457-470 (2011).

5. Aouad, M., Zell, V., Juif, P.E., et al. Etifoxine analgesia in experimental monoarthritis: A combined action that protects spinal inhibition and limits central inflammatory processes. Pain 155(2), 403-412 (2014).