GRM5 and Anxiety: Interestingly, although an intra-AchSh infusion of higher doses of mGlu5 inhibitors (i.e., MPEP or MTEP; 10–30 μg/side) is effective at reducing binge-drinking (Cozzoli et al., 2012) and alcohol reinforcement (Besheer et al., 2009, 2010; Gass and Olive, 2009; Sinclair et al., 2012), the 10 μg/side MTEP dose did not alter anxiety-like behavior on any of our measures in adult water- or alcohol-drinking mice.