Gamma-aminobutyric acid

From Citizendium, the Citizens' Compendium

Gamma aminobutyric acid (GABA) or γ-aminobutyrate, is an inhibitory transmitter in the central nervous system. It is produced from the amino acid glutamate through the action of the enzyme glutamate decarboxylase, and is inactivated by degradation to succinate in a two step mechanism involving the enzymes GABA-glutamate transaminase and succinate semialdehyde dehydrogenase.

Contents 1 Role in clinical pharmacology 1.1 Gamma-aminobutyric acid (GABA) agonists 1.1.1 Barbituates 1.1.2 Benzodiazepines 1.1.2.1 Non-selective agonists 1.1.2.2 BZ1 selective agonists 2 References

Role in clinical pharmacology

Gamma-aminobutyric acid (GABA) agonists

Gamma-aminobutyric acid (GABA) the major inhibitory neurotransmitter in the central nervous system.^[1] Drugs that increase the effect of GABA are called GABAergic.

Many sedatives work by increasing receptiveness of GABA_A receptors.

Barbituates

Barbituates are GABAergic by increasing receptiveness of the GABA_A receptors. Barbituates do this by increasing the duration of openings of channels in the cell membrane.^[1]

• Phenobarbital

Benzodiazepines

Benzodiazepines are also GABAergic by increasing receptiveness of the GABA_A receptors. However, benzodiazepines do this by increasing the frequency of openings of channels in the cell membrane.^[1]

Benzodiazepine receptors are BZ₁ and BZ₂.

Non-selective agonists

• Diazepam (Valium)

BZ₁ selective agonists

• Zaleplon
• Zolpidem

References

1. ↑ ^{1.0 1.1 1.2} Katzung, Bertram G. (2006). Basic and clinical pharmacology. New York: McGraw-Hill Medical Publishing Division. ISBN 0-07-145153-6.