4-Aminobutyric acid
[CAS# 56-12-2]

Identification

• Classification: API >> Digestive system medication >> Antiemetic emetic
• Name: 4-Aminobutyric acid
• Synonyms: 4-Aminobutanoic acid; Piperidic acid; Piperidinic acid; GABA; gamma-Aminobutyric acid
• Molecular Formula: C₄H₉NO₂
• Molecular Weight: 103.12
• CAS Registry Number: 56-12-2
• EC Number: 200-258-6
• SMILES: C(CC(=O)O)CN

Properties

• Water solubility: soluble 1 M (20 °C) (Expl.)
• Density: 1.1±0.1 g/cm³, Calc.^*
• Melting point: 195 °C (Expl.)
• Index of Refraction: 1.465, Calc.^*
• Boiling Point: 248.0±23.0 °C (760 mmHg), Calc.^*
• Flash Point: 103.8±22.6 °C, Calc.^*

^* Calculated using Advanced Chemistry Development (ACD/Labs) Software.

Safety Data

• Hazard Symbols: GHS07 Warning
• Risk Statements: H315-H319-H335
• Safety Statements: P261-P264-P271-P280-P302+P352-P304+P340-P305+P351+P338-P312-P362+P364-P403+P233-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Skin irritation	Skin Irrit.	2	H315
Specific target organ toxicity - single exposure	STOT SE	3	H335
Eye irritation	Eye Irrit.	2	H319
Eye irritation	Eye Irrit.	2A	H319

Discovery and Applications

4-Aminobutyric acid (GABA), a naturally occurring amino acid, plays a vital role in the central nervous system. It is a key inhibitory neurotransmitter in the brain, helping regulate neuronal excitability and contributing to various physiological processes. The discovery and applications of 4-aminobutyric acid have been extensively studied, particularly in the context of its therapeutic benefits and industrial uses.

The discovery of GABA dates back to the early 20th century. In 1883, the compound was first synthesized by the German chemist Albrecht Kossel, but its role as a neurotransmitter was not recognized until later in the 1950s. Its significant biological role was unveiled through research on its presence in the brain and its effects on neuronal activity. As an inhibitory neurotransmitter, GABA helps to reduce neuronal firing and counterbalances the action of excitatory neurotransmitters like glutamate. This function is crucial for maintaining the brain's balance and preventing overstimulation, which can lead to disorders like anxiety and epilepsy.

4-Aminobutyric acid is produced naturally in the body from glutamic acid through the action of the enzyme glutamate decarboxylase. It can also be synthesized artificially for research and therapeutic purposes. GABA receptors, including GABA-A and GABA-B receptors, are widely distributed in the brain and nervous system, with the GABA-A receptor being particularly involved in the sedative and anxiolytic effects of the compound. These receptors are the targets of several therapeutic agents, including benzodiazepines and barbiturates, which enhance the effects of GABA in the brain.

The most well-known application of 4-aminobutyric acid is in the treatment of neurological and psychiatric disorders. Due to its inhibitory function, GABA plays a crucial role in calming excessive neural activity, which is beneficial for conditions such as anxiety, epilepsy, and insomnia. GABA agonists, such as benzodiazepines, are commonly used to treat anxiety and insomnia, as they enhance the inhibitory action of GABA at the GABA-A receptors. Additionally, GABA supplements are marketed as natural sedatives and stress relievers, although their effectiveness in crossing the blood-brain barrier remains debated.

In the realm of research, GABA is also used to study neurotransmission and the functioning of the central nervous system. GABAergic systems are integral to understanding various cognitive functions, including learning, memory, and motor control. GABAergic dysfunction has been implicated in numerous neurological diseases, including Parkinson’s disease, Alzheimer’s disease, and schizophrenia, making GABA a critical area of focus for drug development.

Apart from its therapeutic uses, 4-aminobutyric acid has applications in the food and beverage industry. It is used as a food additive, particularly in functional foods designed to promote relaxation and reduce stress. GABA is sometimes added to dietary supplements marketed for stress relief, cognitive enhancement, and mood regulation. Its purported ability to reduce anxiety and improve sleep quality makes it a popular ingredient in wellness products.

In agriculture, GABA is explored for its potential benefits in plant growth and stress tolerance. Some studies suggest that exogenous application of GABA can enhance plant growth and resistance to environmental stressors like drought and salinity. This area of research is still developing, but it holds promise for improving crop yields and sustainability in agriculture.

Despite its broad range of applications, the use of GABA outside of the body remains limited by its ability to cross the blood-brain barrier. Most of the therapeutic effects of GABA are realized when it is synthesized and introduced into the brain directly, either through drugs or other interventions. Researchers continue to explore ways to enhance the bioavailability of GABA supplements, with the goal of making them more effective for a wider range of conditions.

In conclusion, 4-aminobutyric acid (GABA) is a fundamental neurotransmitter with essential roles in brain function and numerous medical and industrial applications. From its discovery as a key player in neural inhibition to its use in treating neurological disorders and improving mental well-being, GABA continues to be a critical substance in scientific research and therapeutic practices.

References

Kaul, S., Faiman, M. D., and Lunte, C. E., 2011. Determination of GABA, glutamate, dopamine and carbamathione in brain microdialysis samples by micellar electrokinetic chromatography and laser-induced fluorescence (MEKC-LIF). Analytical Methods, 3, 1514.
DOI: 0.1039/c0ay00734j

Durak, A. T., Gökcan, H., and Konuklar, F. A. S., 2011. Theoretical studies on the inactivation mechanism of γ-aminobutyric acid aminotransferase. Organic & Biomolecular Chemistry, 9, 5162.
DOI: 0.1039/c1ob05146f

Shtemenko, A. V., et al., 2009. Synthesis, characterization, in vivo antitumor properties of the cluster rhenium compound with GABA ligands and its synergism with cisplatin. Dalton Transactions, 5132.
DOI: 0.1039/b821041a