Excitotoxicity and new antiglutamatergic strategies in Parkinson's disease and Alzheimer's disease.

N-methyl-D-aspartate (NMDA) receptors play central roles in a number of physiological processes, including long-term potentiation in the hippocampus, synaptogenesis and synaptic plasticity. Excessive NMDA receptor activation has been implicated in the pathophysiology of chronic neurodegenerative diseases, such as Parkinson's disease (PD) and Alzheimer's disease (AD). With the discovery of the heterogeneity of NMDA receptors through molecular biological approaches, new targets have been identified for new-generation NMDA receptor antagonists. This short article focuses on the evidence for the involvement of NMDA receptor subtypes in neurodegenerative disorders and reviews the scarce advances in therapeutic approaches with "selective" NMDA subunit antagonists in PD and AD.