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GABAB
GABAB receptors (GABABR) are G-protein coupled receptors for gamma-aminobutyric acid (GABA), therefore making them metabotropic receptors, that are linked via G-proteins to potassium channels. The changing potassium concentrations hyperpolarize the cell at the end of an action potential. The reversal potential of the GABAB-mediated IPSP (inhibitory postsynaptic potential) is –100 mV, which is much more hyperpolarized than the GABAA IPSP. GABAB receptors are found in the central nervous system and the autonomic division of the peripheral nervous system. The receptors were first named in 1981 when their distribution in the CNS was determined, which was determined by Norman Bowery and his team using radioactively labelled baclofen. Functions GABABRs stimulate the opening of K+ channels, specifically GIRKs, which brings the neuron closer to the equilibrium potential of K+. This reduces the frequency of action potentials which reduces neurotransmitter release. Thus GABAB r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GABBR2
Gamma-aminobutyric acid (GABA) B receptor, 2 (GABAB2) is a G-protein coupled receptor subunit encoded by the GABBR2 gene in humans. Function B-type receptors for the neurotransmitter GABA (gamma-aminobutyric acid) inhibit neuronal activity through G protein-coupled second-messenger systems, which regulate the release of neurotransmitters and the activity of ion channels and adenylyl cyclase. See GABBR1 (MIM 603540) for additional background information on GABA-B receptors. upplied by OMIMref name="entrez" /> Interactions GABBR2 has been shown to interact with GABBR1 Gamma-aminobutyric acid B receptor, 1 (GABAB1), is a G-protein coupled receptor subunit encoded by the ''GABBR1'' gene. Function GABAB1 is a receptor for Gamma-aminobutyric acid. Upon binding, GABAB1 will produce a slow and prolonged inhibito .... See also * GABAB receptor References Further reading * * * * * * * * * * * * * * * * * External links * * G protein-coupled receptors {{transmembr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GABBR1
Gamma-aminobutyric acid B receptor, 1 (GABAB1), is a G-protein coupled receptor subunit encoded by the ''GABBR1'' gene. Function GABAB1 is a receptor for Gamma-aminobutyric acid. Upon binding, GABAB1 will produce a slow and prolonged inhibitory effect. GABAB1 is one part of a heterodimer, which is the GABAB receptor, consisting of it and the related GABAB2 protein. The GABA(B) receptor 1 gene is mapped to chromosome 6p21.3 within the HLA class I region close to the HLA-F gene. Susceptibility loci for multiple sclerosis, epilepsy, and schizophrenia have also been mapped in this region. Alternative splicing of this gene generates 4 transcript variants. Interactions GABBR1 has been shown to interact with ATF4 and GABBR2 Gamma-aminobutyric acid (GABA) B receptor, 2 (GABAB2) is a G-protein coupled receptor subunit encoded by the GABBR2 gene in humans. Function B-type receptors for the neurotransmitter GABA (gamma-aminobutyric acid) inhibit neuronal activity thr .... See ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gamma-Hydroxybutyric Acid
''gamma''-Hydroxybutyric acid (or γ-hydroxybutyric acid (GHB), also known as 4-hydroxybutanoic acid) is a naturally occurring neurotransmitter and a depressant drug. It is a precursor to GABA, glutamate, and glycine in certain brain areas. It acts on the GHB receptor and is a weak agonist at the GABAB receptor. GHB has been used in the medical setting as a general anesthetic and as treatment for cataplexy, narcolepsy, and alcoholism. It is also used illegally as an intoxicant, as an athletic-performance enhancer, as a date-rape drug, and as a recreational drug. It is commonly used in the form of a salt, such as sodium γ-hydroxybutyrate (NaGHB, sodium oxybate, or Xyrem) or potassium γ-hydroxybutyrate (KGHB, potassium oxybate). GHB is also produced as a result of fermentation, and is found in small quantities in some beers and wines, beef, and small citrus fruits. Succinic semialdehyde dehydrogenase deficiency is a disease that causes GHB to accumulate in the blood. Medic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GABAA Receptor
The GABAA receptor (GABAAR) is an ionotropic receptor and ligand-gated ion channel. Its endogenous ligand is γ-aminobutyric acid (GABA), the major inhibitory neurotransmitter in the central nervous system. Upon opening, the GABAA receptor on the postsynaptic cell is selectively permeable to chloride ions (Cl−) and, to a lesser extent, bicarbonate ions (HCO3−). Depending on the membrane potential and the ionic concentration difference, this can result in ionic fluxes across the pore. If the membrane potential is higher than the equilibrium potential (also known as the reversal potential) for chloride ions, when the receptor is activated Cl− will flow into the cell. This causes an inhibitory effect on neurotransmission by diminishing the chance of a successful action potential occurring at the postsynaptic cell. The reversal potential of the GABAA-mediated inhibitory postsynaptic potential (IPSP) in normal solution is −70 mV, contrasting the GABAB IPSP (-100 mV). T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
G Protein-coupled Inwardly-rectifying Potassium Channel
The G protein-coupled inwardly-rectifying potassium channels (GIRKs) are a family of lipid-gated inward-rectifier potassium ion channels which are activated (opened) by the signaling lipid PIP2 and a signal transduction cascade starting with ligand-stimulated G protein-coupled receptors (GPCRs). GPCRs in turn release activated G-protein βγ- subunits ( Gβγ) from inactive heterotrimeric G protein complexes (Gαβγ). Finally, the Gβγ dimeric protein interacts with GIRK channels to open them so that they become permeable to potassium ions, resulting in hyperpolarization of the cell membrane. G protein-coupled inwardly-rectifying potassium channels are a type of G protein-gated ion channels because of this direct interaction of G protein subunits with GIRK channels. The activation likely works by increasing the affinity of the channel for PIP2. In high concentration PIP2 activates the channel absent G-protein, but G-protein does not activate the channel absent PIP2. GIRK ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baclofen
Baclofen, sold under the brand name Lioresal among others, is a medication used to treat muscle spasticity such as from a spinal cord injury or multiple sclerosis. It may also be used for hiccups and muscle spasms near the end of life. It is taken by mouth or by delivery into the spinal canal. Common side effects include sleepiness, weakness, and dizziness. Serious side effects may occur if baclofen is rapidly stopped including seizures and rhabdomyolysis. Use in pregnancy is of unclear safety while use during breastfeeding is probably safe. It is believed to work by decreasing levels of certain neurotransmitters. Baclofen was approved for medical use in the United States in 1977. It is available as a generic medication. In 2020, it was the 108th most commonly prescribed medication in the United States, with more than 6million prescriptions. Medical uses Baclofen is primarily used for the treatment of spastic movement disorders, especially in instances of spinal cord inju ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Norman Bowery
Professor Norman Bowery , (1944 – 25 October 2016) was a British pharmacologist and former Head of Division of Neuroscience and Chair of Pharmacology at the University of Birmingham from 1995 to 2004. He was president of the British Pharmacological Society from 1995 to 1997 and from 1999 to 2000. His research work focused on GABAB receptors, including coining the term ''GABA B'', and extensive studies of GABAB receptor pharmacology. He had previously worked at St Thomas' Hospital, London. He was editor in chief of the journal ''Current Opinion in Pharmacology Currents, Current or The Current may refer to: Science and technology * Current (fluid), the flow of a liquid or a gas ** Air current, a flow of air ** Ocean current, a current in the ocean *** Rip current, a kind of water current ** Current (stre ...''. References British pharmacologists Academics of the University of Birmingham 2016 deaths {{UK-scientist-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neurotransmitter
A neurotransmitter is a signaling molecule secreted by a neuron to affect another cell across a synapse. The cell receiving the signal, any main body part or target cell, may be another neuron, but could also be a gland or muscle cell. Neurotransmitters are released from synaptic vesicles into the synaptic cleft where they are able to interact with neurotransmitter receptors on the target cell. The neurotransmitter's effect on the target cell is determined by the receptor it binds. Many neurotransmitters are synthesized from simple and plentiful precursors such as amino acids, which are readily available and often require a small number of biosynthetic steps for conversion. Neurotransmitters are essential to the function of complex neural systems. The exact number of unique neurotransmitters in humans is unknown, but more than 100 have been identified. Common neurotransmitters include glutamate, GABA, acetylcholine, glycine and norepinephrine. Mechanism and cycle Synthes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
G Protein-coupled Receptor
G protein-coupled receptors (GPCRs), also known as seven-(pass)-transmembrane domain receptors, 7TM receptors, heptahelical receptors, serpentine receptors, and G protein-linked receptors (GPLR), form a large group of evolutionarily-related proteins that are cell surface receptors that detect molecules outside the cell and activate cellular responses. Coupling with G proteins, they are called seven-transmembrane receptors because they pass through the cell membrane seven times. Text was copied from this source, which is available under Attribution 2.5 Generic (CC BY 2.5) license. Ligands can bind either to extracellular N-terminus and loops (e.g. glutamate receptors) or to the binding site within transmembrane helices (Rhodopsin-like family). They are all activated by agonists although a spontaneous auto-activation of an empty receptor can also be observed. G protein-coupled receptors are found only in eukaryotes, including yeast, choanoflagellates, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterodimer
In biochemistry, a protein dimer is a macromolecular complex formed by two protein monomers, or single proteins, which are usually non-covalently bound. Many macromolecules, such as proteins or nucleic acids, form dimers. The word ''dimer'' has roots meaning "two parts", '' di-'' + '' -mer''. A protein dimer is a type of protein quaternary structure. A protein homodimer is formed by two identical proteins. A protein heterodimer is formed by two different proteins. Most protein dimers in biochemistry are not connected by covalent bonds. An example of a non-covalent heterodimer is the enzyme reverse transcriptase, which is composed of two different amino acid chains. An exception is dimers that are linked by disulfide bridges such as the homodimeric protein NEMO. Some proteins contain specialized domains to ensure dimerization (dimerization domains) and specificity. The G protein-coupled cannabinoid receptors have the ability to form both homo- and heterodimers with several typ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ca Channels
A calcium channel is an ion channel which shows selective permeability to calcium ions. It is sometimes synonymous with voltage-gated calcium channel, although there are also ligand-gated calcium channels. Comparison tables The following tables explain gating, gene, location and function of different types of calcium channels, both voltage and ligand-gated. Voltage-gated Ligand-gated *the ''receptor-operated calcium channels'' (in vasoconstriction) **P2X receptors Page 479 Pharmacology L-type calcium channel blockers are used to treat hypertension. In most areas of the body, depolarization is mediated by sodium influx into a cell; changing the calcium permeability has little effect on action potentials. However, in many smooth muscle tissues, depolarization is mediated primarily by calcium influx into the cell. L-type calcium channel blockers selectively inhibit these action potentials in smooth muscle which leads to dilation of blood vessels; this in turn corrects hypertens ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
