Glutamate-glutamine Cycle

In biochemistry, the glutamate-glutamine cycle is a sequence of events by which an adequate supply of the neurotransmitter glutamate is maintained in the central nervous system. Neurons are not able to perform new synthesis of the neurotransmitter glutamate and γ-aminobutyric acid (GABA) from glucose. Discoveries of glutamine and glutamate pools within intercellular compartments led to suggestions of the glutamate-glutamine cycle working between neurons and astrocytes. The glutamate/GABA-glutamine cycle is a metabolic pathway that describes the release of glutamate or GABA from neurons and then taken up into astrocytes(star shaped glial cells). In return, astrocytes release glutamine to be taken up into neurons for use as a precursor to the synthesis of glutamate or GABA.