The role of glutamate in central nervous system health and disease--a review.

Glutamate is the principal excitatory neurotransmitter in the brain. Knowledge of the glutamatergic synapse has advanced enormously over the last 10 years, primarily through application of cellular electrophysiological and molecular biological techniques to the study of glutamate receptors and transporters. There are three families of ionotropic glutamate receptors with intrinsic cation permeable channels. There are also three groups of metabotropic, G-protein-coupled glutamate receptors that can modify neuronal excitability. There are also two glial glutamate transporters and three neuronal transporters in the brain. Endogenous glutamate may contribute to the brain damage occurring acutely after traumatic brain injury as well as having a role in the excitatory imbalance present in epileptic conditions and contributing to the pathophysiology of hepatic encephalopathy in animals. Understanding the role of glutamate in these neurological diseases may highlight treatment potentials of antagonists to glutamatergic transmission. This paper presents a review of the literature of glutamate and its role in neurological function and disease.