For example, whereas germline mGluR5 KO mice adopted an active coping stress style upon testing in the FST, which was suggested as an “antidepressant” response [25], several converging lines of evidence emerging from both exposure to escapable and inescapable stressors confirmed an endophenotype for stress-induced depression-like behavior in these mice [26]. This evidence concerns the gene GRM5 and major depressive disorder.