The blockade of GABA transporter 1 (GAT1) or GABA transporter 3 (GAT3) in the LHb upregulated extracellular GABA levels and caused greater GABAergic inhibition, downregulating LHb neuronal activity and firing rate of LHb neurons, resulting in an improvement in depression-like behaviors in PD rats (119). This evidence concerns the gene SLC6A1 and Parkinson disease.