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There are 4 glossary search results for:   activation gate




Definition:
Proposed model for the inactivation of some voltage-gated ion channels. According to this model, after channel opening, the pore of the open channel is plugged by a globular cytoplasmic portion of the channel protein. The globular portion (ball of amino acids) is tethered to the rest of the protein by a linker part (chain of amino acids).

Related glossary terms/phrases:
Channel inactivation

See also:
Neuronal Action Potential - Important Features of the Neuronal Action Potential



Abbreviation:
GABA

Definition:
GABA is an inhibitory amino acid neurotransmitter in the central and peripheral nervous systems. It is the most abundant inhibitory neurotransmitter in the nervous system. During embryonic development, GABA acts as an excitatory neurotransmitter at some central synapses. GABA is a classical neurotransmitter. Its action is exerted via the activation of GABAA, GABAB, and GABAC receptors. GABAA and GABAC receptors are ligand-gated chloride channels, whereas GABAB receptors are G protein coupled receptors. At GABAergic synapses, the action of GABA is terminated by GABA transporters (GAT), which transport GABA from the extracellular space in synaptic and extrasynaptic regions into neurons and glia.



Definition:
Glutamate (Glu, E) is one of the standard twenty (20) amino acids used by cells to synthesize peptides, polypeptides, and proteins. It has a molecular weight of 147.13 g/mol. Its side chain has a pKa of 4.07 and, therefore, glutamate has a net negative charge at physiological pH.

In the nervous system, glutamate is an excitatory amino acid neurotransmitter. In fact, glutamate is the most abundant excitatory neurotransmitter in the nervous system. Glutamate is a classical neurotransmitter. Its action is exerted via the activation of glutamate receptors (GluR), some of which are ligand-gated ion channels (ionotropic receptors), and some are G protein coupled receptors (GPCRs, metabotropic receptors). At glutamatergic synapses, the action of glutamate is terminated by glutamate transporters (EAAT, excitatory amino acid transporter), which transport glutamate from the extracellular space in synaptic and extrasynaptic regions into neurons and glia.



Definition:
Glycine (Gly, G) is one of the standard twenty (20) amino acids. At a molecular weight of 75.07 g/mol, it is the smallest of the 20 amino acids used by cells to synthesize peptides, polypeptides, and proteins.

In the nervous system, glycine is also an inhibitory amino acid neurotransmitter. Glycinergic synapses are most commonly found in brain stem and spinal cord circuits. Glycine is a classical neurotransmitter. Its action is exerted via the activation of ionotropic glycine receptors (GlyR), which are ligand-gated chloride channels. At glycinergic synapses, the action of glycine is terminated by glycine transporters (GlyT), which transport glycine from the extracellular space in synaptic and extrasynaptic regions into neurons and glia.









Posted: Sunday, March 31, 2013
Last updated: Friday, August 28, 2015