GRM5 and depressive disorder: After the glial ablation model of depression was developed [18], the antidepressant-like effect of mGluR5 antagonist MTEP [38], prefrontal cortex deep brain stimulation [39], Y5 receptor antagonist Lu AA33810 [40], Harmine [41], ZL006 [42], and ginsenoside Rf [43] were tested.