PSYCH 3AB3 Lecture Notes - Synaptic Vesicle, Chemical Synapse, Axon Terminal
Document Summary
Neurotransmitters: most neurotransmitters fall into one of three chemical categories: Secretory granules and synaptic vesicles are frequently observed in the same axon terminals: different neurons in the brain release different neurotransmitters. Fast synaptic transmission at most cns synapses is mediated by the amino acids glutamate (glu), gamma-aminobutyric acid (gaba) and glycine (gly). The amine acetylcholine (ach) mediates fast synaptic transimission at all neuromuscular junctions. Cns and in the periphery are mediated by transmitters from all three chemical categories. Concentrating these neurotransmitters is the job of transporters: different mechanisms are used to synthesize and store peptides in secretory granules. Generally, a long peptide synthesized in the rough er is split in the golgi apparatus, and of the smaller peptide fragments is the active neurotransmitter. Secretory granules containing the peptide neurotransmitter bud off the golgi apparatus and are carried to the axon terminal by axoplasmic transport.