Glycine receptor
The glycine receptor (abbreviated as GlyR or GLR) is the
The receptor can be activated by a range of simple
The protein
History
Glycine and its receptor were first suggested to play a role in inhibition of cells in 1965.[8] Two years later, experiments showed that glycine had a hyperpolarizing effect on spinal motor neurons[9] due to increased chloride conductance through the receptor.[10] Then, in 1971, glycine was found to be localized in the spinal cord using autoradiography.[11] All of these discoveries resulted in the conclusion that glycine is a primary inhibitory neurotransmitter of the spinal cord that works via its receptor.
Arrangement of subunits
Strychnine-sensitive GlyRs are members of a family of
Function
Adults
In mature adults, glycine is a inhibitory neurotransmitter found in the spinal cord and regions of the brain.[15] As it binds to a glycine receptor, a conformational change is induced, and the channel created by the receptor opens.[17] As the channel opens, chloride ions are able to flow into the cell which results in hyperpolarization. In addition to this hyperpolarization, which decreases the likelihood of action potential propagation, glycine is also responsible for decreasing the release of both inhibitory and excitatory neurotransmitters as it binds to its receptor.[18] This is called the "shunting" effect and can be explained by Ohm's Law. As the receptor is activated, the membrane conductance is increased and the membrane resistance is decreased. According to Ohm's Law, as resistance decreases, so does voltage. A decreased postsynaptic voltage results in a decreased release of neurotransmitters.[18]
Embryos
In developing embryos, glycine has the opposite effect as it does in adults. It is an excitatory neurotransmitter.
Glycine receptors in diseases
Disruption of GlyR surface expression or reduced ability of expressed GlyRs to conduct chloride ions results in the rare neurological disorder,
Ligands
Agonists
- β-Alanine
- D-Alanine
- Gelsemine
- Glycine
- Hypotaurine
- Ivermectin[20]
- L-Alanine
- L-Proline
- L-Serine
- Milacemide
- Quisqualamine
- Sarcosine
- Taurine
- THC
- L-Theanine
Positive Allosteric Modulators
Antagonists
References
- ^ PMID 15383648.
- PMID 9131721.
- PMID 19564396.
- PMID 21460829.
- ^ PMID 14715953.
- PMID 9812897.
- PMID 24920633.
- PMID 5866625.
- S2CID 4198837.
- PMID 4384497.
- PMID 4329648.
- S2CID 205209809.
- S2CID 25411536.
- ^ S2CID 42056647.
- ^ PMID 9131721.
- PMID 26255765.
- S2CID 41022948.
- ^ S2CID 247871.
- ^ Online Mendelian Inheritance in Man (OMIM): STIFF-PERSON SYNDROME; SPS - 184850
- PMID 11278873.
External links
- Glycine+Receptors at the U.S. National Library of Medicine Medical Subject Headings (MeSH)