GRM4 and Parkinson disease: Furthermore, the novel mGlu4 PAMs (1S,2R)-2-[(aminooxy)methyl]-N-(3,4-dichlorophenyl)cyclohexane-1-carboxamide (Lu AF21934) and 4-methyl-N-[5-methyl-4-(1H-pyrazol-4-yl)-1,3-thiazol-2-yl]pyrimidin-2-amine (ADX88178) have been shown to promote anxiolytic effects in acute rodent models [e.g., stress-induced hyperthermia (SIH), four-plate test (FPT) and marble-burying test (MBT)], and to be effective in several PD models (Kalinichev et al., 2014).