GRM5 and Focal cortical dysplasia: In patients with intractable epilepsy associated with focal cortical dysplasia astrocytes show functional plasticity by increasing the expression of purinergic receptors (P2Y1, P2Y2, P2Y4), metabotropic glutamate receptors (mGluR1 and mGluR5) and potassium channels (Kv4.2 and Kir4.1) [11].