Synaptic Transmission
From Wikiversity
Here is the link to the ITunes U Lecture from Berkeley. Synaptic Transmission
I will post my notes soon. Please feel free to add details or make changes where necessary. Contact me via email if you need help. Thanks, April
[edit] Channel Receptor Types (Overview)
There are several types of known synaptic channel types. [1]
- Ionotropic channels involved in (or inhibiting) an action potential or train of action potentials, are: M-currents (or M-channels), T-currents, L-currents, C-currents, AHP currents, N-currents, GIRK channels, GABAA, GABAB. These can exist presynaptically or postsynaptically.
- G-Protein Coupled Receptors (GPCRs) are metabotropic second messenger channels (usually postsynaptic). Ordinarily, a ligand will bind and the alpha subunit will have one effect, and the beta-gamma subunit may have another. The GPCR type is generally named after its alpha unit's effect and are referred to as Gs (or Gαs), Gq, Gi, and Go (the latter 2 are frequently lumped together as Gi/o. In many sensory organs, the GPCR is a 7-transmembrane protien unit comprised of alpha helices. There are certain exceptions.
- Noteworthy example: Interneurons may innervate the presynaptic sensory terminals (as in Aplysia) [2], to use a GPCR to alter motor neuron output (short-term facilitation) via change in open channel probability. Subsequent stimulation of transcription further affects long-term facilitation.
Author's note: this is a broad overview of a few types of synaptic transmission with a few examples that do not divulge much detail. I included key words to encourage pages to be created as branches, explaining in more detail, each part of synaptic transmission.
[edit] References
- ↑ Nicholls, John G.; Martin, A. Robert; Fuchs, Paul A.; Brown, David A.; Diamond, Mathew E.; Weisblat, David A. (2012). From Neuron to Brain (Fifth ed.). pp. 229, 342.
- ↑ (10 Feb 2010) "Aplysia CPEB can form prion-like multimers in sensory neurons that contribute to long-term facilitation". Cell 140 (3): 421-35. doi:10.1016/j.cell.2010.01.008. PMID 20144764.
