GABA γ-Aminobutyric acidAya Ali

431203717

Outline :GABA: Mechanism of action Synthesis. Receptors . Function . Deficiency. Disease related . Conclusion

GABA

 GABA acts at inhibitory synapse in the brain by binding to specific transmembrane  receptor in the plasma membrane  of both pre- and postsynaptic neuronal processes.

It is most highly concentrated in the substantia nigra & globus pallidus nuclei of the basal ganglia, followed by the hypothalamus, the periaqueductal grey matter. 

Fig (1)

Mechanism of Action

open chloride receptors-channels induce cellular hyperpolarisation by increasing intracellular concentration of chloride

Synthesis of GABA

GABA exerts its effects via two types of receptors: GABA-A and GABA-B receptors

GABA Receptor

GABA-A

GABA-B Activation of presynaptic GABA-B receptors

decreases the release of GABA and of different transmitters.

Activation of postsynaptic GABA-B receptors modulates the opening of potassium channels, which induces an intracellular potassium exit and consequently a membrane hyperpolarisation. 

GABA Function Relieving anxiety. Improving mood. Relieving premenstrual syndrome (PMS). Regulating the release of sex hormones.

Treating attention deficit-hyperactivity disorder (ADHD).

Promoting lean muscle growth. Burning fat. Stabilizing blood pressure. Relieving pain. lower elevated blood sugar levels in

diabetics.

GABA Functions… cont

Deficiency of GABA

It has been suggested that a shortage of GABA may cause panic attacks, since an intake of tranquilizers can increase the level of GABA in the body. GABA may also be effective in treating PMS in women.

Health problems can GABA Deficiency cause

Insomnia

Depression Mood disorders Excessive stress Hypertension Atherosclerosis Motion sickness

low levels of digestive enzymesADHDEpileptic seizuresPanic disordersBronchitisGrowth hormone stimulation

Reference http://

www.benbest.com/science/anatmind/anatmd10.html#gaba

http://

www.pharmacorama.com/en/Sections/Gaba.php

Conclusion

GABA is an amino acid made in brain cells from glutamate. It functions as an inhibitory neurotransmitter, meaning it blocks nerve impulses. Without GABA, nerve cells fire too often and too easily.