γ-Hydroxybutyric acid, also known as gamma-hydroxybutyric acid, GHB, or 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. The substance is also used illicitly for various reasons, including as a performance-enhancing drug, date rape drug, and as a recreational drug.
GABA is the chief inhibitory neurotransmitter in the developmentally mature mammalian central nervous system. Its principal role is reducing neuronal excitability throughout the nervous system.
Depressants, colloquially known as "downers" or central nervous system (CNS) depressants, are drugs that lower neurotransmission levels, decrease the electrical activity of brain cells, or reduce arousal or stimulation in various areas of the brain. Some specific depressants do influence mood, either positively or negatively, but depressants often have no clear impact on mood. In contrast, stimulants, or "uppers", increase mental alertness, making stimulants the opposite drug class from depressants. Antidepressants are defined by their effect on mood, not on general brain activity, so they form an orthogonal category of drugs.
γ-Butyrolactone (GBL) or gamma-butyrolactone is an organic compound with the formula O=CO(CH2)3. It is a hygroscopic, colorless, water-miscible liquid with a weak characteristic odor. It is the simplest 4-carbon lactone. It is mainly used as an intermediate in the production of other chemicals, such as N-methyl-2-pyrrolidone.
Vigabatrin, sold under the brand name Sabril among others, is a medication used in the management and treatment of infantile spasms and refractory complex partial seizures.
Sodium oxybate, sold under the brand name Xyrem among others, is a medication used to treat symptoms of narcolepsy: sudden muscle weakness and excessive daytime sleepiness. It is used sometimes in France and Italy as an anesthetic given intravenously; it is also approved and used in Italy and in Austria to treat alcohol dependence and alcohol withdrawal syndrome.
Succinic semialdehyde dehydrogenase deficiency (SSADHD) is a rare autosomal recessive disorder of the degradation pathway of the inhibitory neurotransmitter γ-aminobutyric acid, or GABA. The disorder has been identified in approximately 350 families, with a significant proportion being consanguineous families. The first case was identified in 1981 and published in a Dutch clinical chemistry journal that highlighted a number of neurological conditions such as delayed intellectual, motor, speech, and language as the most common manifestations. Later cases reported in the early 1990s began to show that hypotonia, hyporeflexia, seizures, and a nonprogressive ataxia were frequent clinical features as well.
In enzymology, a 4-hydroxybutyrate dehydrogenase (EC 1.1.1.61) is an enzyme that catalyzes the chemical reaction
In enzymology, a succinate-semialdehyde dehydrogenase (SSADH) (EC 1.2.1.24) is an enzyme that catalyzes the chemical reaction
γ-Amino-β-hydroxybutyric acid (GABOB), also known as β-hydroxy-γ-aminobutyric acid (β-hydroxy-GABA), sold under the brand name Gamibetal among others, is an anticonvulsant which is used for the treatment of epilepsy in Europe, Japan, and Mexico. It is a GABA analogue, or an analogue of the neurotransmitter γ-aminobutyric acid (GABA), and has been found to be an endogenous metabolite of GABA.
In enzymology, 4-aminobutyrate transaminase, also called GABA transaminase or 4-aminobutyrate aminotransferase, or GABA-T, is an enzyme that catalyzes the chemical reaction:
Succinate-semialdehyde dehydrogenase, mitochondrial is an enzyme that in humans is encoded by the ALDH5A1 gene.
The γ-hydroxybutyrate (GHB) receptor (GHBR), originally identified as GPR172A, is an excitatory G protein-coupled receptor (GPCR) that binds the neurotransmitter and psychoactive drug γ-hydroxybutyric acid (GHB). As solute carrier family 52 member 2 (SLC52A2), it is also a transporter for riboflavin.
NCS-382 is a moderately selective antagonist for the GHB receptor. It blocks the effects of GHB in animals and has both anti-sedative and anticonvulsant effects. It has been proposed as a treatment for GHB overdose in humans as well as the genetic metabolic disorder succinic semialdehyde dehydrogenase deficiency (SSADHD), but has never been developed for clinical use.
γ-Hydroxyvaleric acid (GHV), also known as 4-methyl-GHB, is a designer drug related to γ-hydroxybutyric acid (GHB). It is sometimes seen on the grey market as a legal alternative to GHB, but with lower potency and higher toxicity, properties which have tended to limit its recreational use.
The gab operon is responsible for the conversion of γ-aminobutyrate (GABA) to succinate. The gab operon comprises three structural genes – gabD, gabT and gabP – that encode for a succinate semialdehyde dehydrogenase, GABA transaminase and a GABA permease respectively. There is a regulatory gene csiR, downstream of the operon, that codes for a putative transcriptional repressor and is activated when nitrogen is limiting.
4-aminobutyrate---pyruvate transaminase is an enzyme with systematic name 4-aminobutanoate:pyruvate aminotransferase. This enzyme is a type of GABA transaminase, which degrades the neurotransmitter GABA. The enzyme catalyses the following chemical reaction
4-Aminobutyrate aminotransferase is a protein that in humans is encoded by the ABAT gene. This gene is located in chromosome 16 at position of 13.2. This gene goes by a number of names, including, GABA transaminase, GABAT, 4-aminobutyrate transaminase, NPD009 etc. This gene is mainly and abundant located in neuronal tissues. 4-Aminobutyrate aminotransferase belongs to group of pyridoxal 5-phosphate-dependent enzyme which activates a large portion giving reaction to amino acids. ABAT is made up of two monomers of enzymes where each subunit has a molecular weight of 50kDa. It is identified that almost tierce of human synapses have GABA. GABA is a neurotransmitter that has different roles in different regions of the central and peripheral nervous systems. It can be found also in some tissues that do not have neurons. In addition, GAD and GABA-AT are responsible in regulating the concentration of GABA.
4-Aminobutanal, also known as γ-aminobutyraldehyde, 4-aminobutyraldehyde, or GABA aldehyde, is a metabolite of putrescine and a biological precursor of γ-aminobutyric acid (GABA). It can be converted into GABA by the actions of diamine oxidase (DAO) and aminobutyraldehyde dehydrogenase (ABALDH). Putrescine is converted into ABAL via monoamine oxidase B (MAO-B). However, biosynthesis of GABA from polyamines like putrescine is a minor metabolic pathway in the brain.
4-Amino-1-butanol, or 4-aminobutanol, also known as 4-hydroxybutylamine, is an alkanolamine and an analogue and precursor of the neurotransmitter γ-aminobutyric acid (GABA).
