Fenobam is a noncompetitive antagonist and inverse agonist of metabotropic glutamate receptor 5 (mGluR5) that binds to an allosteric site.1 It inhibits intracellular calcium mobilization induced by the glutamate analog quisqualate in HEK293 cells expressing the human receptor (IC50 = 58 nM) and inhibits basal activity of mGluR5 in a cell-based assay (IC50 = 84 nM).1 Fenobam (10 and 30 mg/kg) reduces stress-induced hyperthermia in mice and increases drinking time in the Vogel conflict test in rats when administered at a dose of 30 mg/kg, indicating anxiolytic-like activity. It induces analgesia in the formalin test in mice when administered at a dose of 30 mg/kg.2
1.Porter, R.H.P., Jaeschke, G., Spooren, W., et al.Fenobam: A clinically validated nonbenzodiazepine anxiolytic Is a potent, selective, and noncompetitive mGlu5 receptor antagonist with inverse agonist activityJ. Pharmacol. Exp. Ther.315(2)711-721(2005) 2.Montana, M.C., Conrardy, B.A., Cavallone, L.F., et al.Metabotropic glutamate receptor 5 antagonism with fenobam: Examination of analgesic tolerance and side effect profile in miceAnesthesiology115(6)1239-1250(2011)