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 |