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There are 2 glossary search results for:   H chain




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



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.









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