For this purpose, we have combined low doses of the mGluR5 antagonist MTEP (1.25 mg/kg; Belozertseva et al. 2007) and ketamine (1 mg/kg; Podkowa et al. 2016), and tested the effects of this cocktail drug on behavioral despair, anxiety-like behavior, and fear extinction. The gene discussed is GRM5; the disease is Anxiety.