Moreover, the injection of exogenous DA into SNpr induced seizures and a significant reduction of gene expression for GluR1, GluR2 and NMDAR1 subunits in rat hippocampal subfields including CA1 through CA4 and DG [45], which indicated hippocampus-SNpr pathway may be involved in the mechanism of epilepsy. Here, GRIN1 is linked to epilepsy.