In a model of Parkinson’s disease (6-OH-dopamine hemi-lesioned rat), the authors wanted to quantify the quantity of AT2/AT1 dimers in striatal sections of naïve and 6-OH-dopamine hemi-lesioned rats, treated or not with L-DOPA and divided into two groups: those that are dyskinetic and those that are resistant to L-DOPA-induced dyskinesia. This evidence concerns the gene AGTR2 and drug-induced dyskinesia.