GABAA Receptor
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A GABAA Receptor is an Ionotropic Receptor that ...
- See: Picrotoxin, Ionotropic Receptor, Ligand-Gated Ion Channel, Ion Channel, Endogenous, Ligand (Biochemistry), γ-Aminobutyric Acid, Neurotransmitter, Central Nervous System, Chloride, Neurotransmission, Action Potential.
References
2019
- (Wikipedia, 2019) ⇒ https://en.wikipedia.org/wiki/GABAA_receptor Retrieved:2019-4-18.
- 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 activation, the GABAA receptor selectively conducts Cl− through its pore. Cl- will flow out of the cell if the internal voltage is less than resting potential and Cl- will flow in if it is more than resting potential (i.e. -75 mV) . This causes an inhibitory effect on neurotransmission by diminishing the chance of a successful action potential occurring. The reversal potential of the GABAA-mediated inhibitory postsynaptic potential (IPSP) in normal solution is −70 mV, contrasting the GABAB IPSP (-100 mV). The active site of the GABAA receptor is the binding site for GABA and several drugs such as muscimol, gaboxadol, and bicuculline. The protein also contains a number of different allosteric binding sites which modulate the activity of the receptor indirectly. These allosteric sites are the targets of various other drugs, including the benzodiazepines, nonbenzodiazepines, neuroactive steroids, barbiturates, alcohol (ethanol), inhaled anaesthetics, and picrotoxin, among others.
GABAA receptors occur in all organisms that have a nervous system. To a limited extent the receptors can be found in non-neuronal tissues. Due to their wide distribution within the nervous system of mammals they play a role in virtually all brain functions.
- 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 activation, the GABAA receptor selectively conducts Cl− through its pore. Cl- will flow out of the cell if the internal voltage is less than resting potential and Cl- will flow in if it is more than resting potential (i.e. -75 mV) . This causes an inhibitory effect on neurotransmission by diminishing the chance of a successful action potential occurring. The reversal potential of the GABAA-mediated inhibitory postsynaptic potential (IPSP) in normal solution is −70 mV, contrasting the GABAB IPSP (-100 mV). The active site of the GABAA receptor is the binding site for GABA and several drugs such as muscimol, gaboxadol, and bicuculline. The protein also contains a number of different allosteric binding sites which modulate the activity of the receptor indirectly. These allosteric sites are the targets of various other drugs, including the benzodiazepines, nonbenzodiazepines, neuroactive steroids, barbiturates, alcohol (ethanol), inhaled anaesthetics, and picrotoxin, among others.