Excitatory amino acids

{| class="wikitable" align="right" width="360px"
 * Synapse diag1.svg || Activity at an axon terminal: Neuron A is transmitting a signal at the axon terminal to neuron B (receiving).  Features:  1. Mitochondrion.  2. synaptic vesicle with neurotransmitters.  3. Autoreceptor.  4. Synapse with neurotransmitter released (serotonin). 5. Postsynaptic receptors activated by neurotransmitter (induction of a postsynaptic potential). 6. Calcium channel. 7. Exocytosis of a vesicle. 8. Recaptured neurotransmitter. |}

An excitatory amino acids is an amino acids that acts as a amino acid neurotransmitter which has an excitatory effect at the synapse

An amino acid neurotransmitter is a chemical substance which is able to transmit a nerve message across a synapse. Neurotransmitters (chemicals) are packaged into vesicles that cluster beneath the axon terminal membrane on the presynaptic side of a synapse in a process called endocytosis. Amino acid neurotransmitter release (exocytosis) is dependent upon calcium Ca2+ and is a presynaptic response.

Some EAA are L-Glutamate, L-Aspartate, L-Cysteine, and L-Homocysteine. These neurotransmitter systems will activate post-synaptic cells. Some IAA include GABA, Glycine, β-Alanine, and Taurine. The IAA depress the activity of post-synaptic cells.