As shown in Figure 5, in the L-dopa treatment group, we detected a robust increased phospho-ERK1/2 level in the 6-OHDA-lesioned striatum of rats with serious dyskinetic movements; however, in the L-dopa + JQ1 treatment group, phospho-ERK1/2 increased mildly in the lesioned striatum of rats with mild dyskinesia (p < 0.001 vs. the Veh group, p < 0.01 vs. L-dopa treatment group). Here, MAPK3 is linked to drug-induced dyskinesia.