Gamma-aminobutyric acid, structure

Gamma aminobutyric acid (GABA) receptors are located on the postsynaptic membranes of inhibitory synapses of both vertebrates and insects and contain within their membrane-spanning structure a chloride ion channel. They are found in both vertebrate brains and invertebrate cerebral ganglia (sometimes referred to as brains) as well as in insect muscles. Particular attention has been given to one form of this receptor—the GABA-A receptor—as a target for novel insecticides (Eldefrawi and Eldefrawi 1990). It is found both in insect muscle and vertebrate brain. The remainder of this description will be restricted to this form. 

In essence, all of the older benzodiazepines that are structurally related to chlordiazepoxide and diazepam are termed 1,4-benzodiazepines. The chemical structure of some commonly used benzodiazepines is shown in Figure 9.2. They enhance the actions of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA) in the brain. As a consequence, they affect the activities of the cerebellum (concerned with balance and coordination), the limbic areas of the brain and the cerebral cortex (thought and decision making, fine movement control). 

Acamprosate (calcium acetylhomotaurinate) is a synthetic compound with a similar chemical structure to that of gamma-aminobutyric acid. It is the... 

Kuriyama, T., Schmidt, T.J., Okuyama, E. and Ozoe, Y. (2002) Structure-activity relationships of seco-prezizaane terpenoids in gamma-aminobutyric acid receptors of houseflies and rats. Bioorganic and Medicinal Chemistry 1 0(6), 1 873-1 881. 

Although structurally related to gamma-aminobutyric acid (GABA), no known direct actions on GABA or its receptors... 

Baclofen is structurally related to gamma-aminobutyric acid (GABA), an inhibitory central nervous system transmitter it inhibits reflex activity mainly in the spinal cord. Baclofen reduces spasticity and flexor spasms, but as it has no action on voluntary muscle power, function is commonly not improved. Ambulant patients may need their leg spasticity to provide support and reduction of spasticity may expose the weakness of the limb. It benefits some cases of trigeminal neuralgia. Baclofen is given orally (tVj 3 h). 

Ibotenic acid is structurally similar to glutamic acid, whereas muscimol closely resembles gamma-aminobutyric acid (GABA). Muscimol has an affinity for GABA receptors in the central nervous system, functioning as a false neurotransmitter, and appears to mimic the effects of GABA. 

DeLorey TM (1992) Gamma-aminobutyric acid A receptor structure and funetion. J. Biol. Chem. 267, 16747-16750. 

Ozoe, Y., Yagi, K., Nakamura, M., Akamatsu, M., Miyake, T., and Matsumura, F. 2000. Fipronil-related heterocyclic compounds structure-activity relationships for interaction with gamma-aminobutyric acid- and voltage-gated ion channels and insecticidal action. Pest. Biochem. Physiol., 66, 92-104. 

Compound 24 is a gamma-aminobutyric acid (GABA) receptor modulator that interacts with the GABA-A sub-type which is, in turn, the same locale where the classical benzodiazepine anxiolytics are also thought to interact (diazepam or Valium being a common benzodiazepine structure shown above as 57). Although 24 is classed as a nonbenzodiazepine sedative-hypnotic because it has... 

Gamma-aminobutyric acid (GABA) which derives from glutamic acid via decarboxylation is the most important inhibitory neurotransmitter of inhibitory neurons of the CNS, most of them intemeurons. Approximately 30% of all central synapses are GABAergic. Pentameric GABAa receptors (similar structure as nAChR Fig. 4) modulate a CF channel,... 

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