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n. a salt or ester of the amino acid glutamic acid that serves as the predominant excitatory neurotransmitter in the brain. Glutamate plays a critical role in cognitive, motor, and sensory functions. It exerts its effects by binding to glutamate receptors on neurons. Excessive activity of glutamate at these receptors is associated with damage to nerve tissue (neurotoxicity) and cell death (see excitotoxicity), possibly the result of calcium ions flooding into the cell following overstimulation of NMDA receptors.

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Psychology term of the day

May 26th 2024

GABAA receptor

GABAA receptor

one of the two main types of receptor protein that bind the neurotransmitter gamma-aminobutyric acid (GABA), the other being the GABAB receptorgabab-receptor. It is located at most synapses of most neurons that use GABA as a neurotransmitter. The predominant inhibitory receptor in the central nervous system, it functions as a chloride channel (see ion channel). GABA agonists, such as the barbiturates and benzodiazepines, enhance the binding of GABA to GABAA receptors, allowing for increased conductance of chloride through the ion channel and thereby hyperpolarizing the neuron and inhibiting its activity. GABA antagonists, such as bicuculline and picrotoxin, block the inhibitory effects of GABA at this receptor. Many other substances, including alcohol (ethanol), are thought to exert at least part of their effect via interaction at the GABAA receptor.