Glutamic acid
Glutamate is also a neurotransmitter (see below), which makes it one of the most abundant molecules in the brain. Malignant brain tumors known as glioma or glioblastoma exploit this phenomenon by using glutamate as an energy source, especially when these tumors become more dependent on glutamate due to mutations in the gene "IDH1".
Animal model of schizophrenia
Glutamate is the most abundant excitatory neurotransmitter in vertebrate nervous systems. Evidence for the involvement of glutamate in schizophrenia includes analogous symptoms which are produced by glutamate NMDA receptor antagonists such as phencyclidine (PCP) and ketamine. PCP is a non-competitive NMDA receptor antagonist which produces hallucinations and delusions in normal subjects. In rat models, disturbed cognition, deficits in social interaction, locomotor anomalies, and prepulse inhibition deficits are seen on acute administration of PCP. Evidence that persistent PCP use and abuse in humans results in lasting deficits beyond the period of treatment has led to the suggestion that this regime in rodents may be a more accurate model of schizophrenia than acute administration. A number of protocols for chronic PCP animal models have been developed, with different effects. The effects of some, but not all protocols can be reversed by treatment with antipsychotics. In a primate model, PCP was found to induce cognitive impairments which were reversed with clozapine.