An amino acid neurotransmitter is an amino acid 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.[1]
Amino acid neurotransmitter release (exocytosis) is dependent upon calcium Ca2+ and is a presynaptic response.
Excitatory amino acids (EAA) will activate post-synaptic cells.[2] inhibitory amino acids (IAA) depress the activity of post-synaptic cells.[2]
Amino acid[3][4] | Excitatory or inhibitory |
---|---|
Aspartic acid | Excitatory |
β-alanine | Inhibitory |
Cysteine | Excitatory |
GABA (adult human brain) | Inhibitory (adult); excitatory (developing) |
Glycine | Inhibitory |
Glutamic acid | Excitatory |
Homocysteine | Excitatory |
Taurine | Inhibitory |