Activity-Dependent Regulation of Glucose Transporters

Neuronal activity demands an increase of glucose flux through the blood-brain barrier into the gliovascular unit. The delivery of glucose is controlled by facilitative glucose transporters of the GLUT family, located in the plasma membrane of endothelium, astrocytes, and neurons. Experiments in cultured cells have shown that the neurotransmitter glutamate stimulates the astrocytic glucose transporter GLUT1 and inhibits the neuronal glucose transporter GLUT3, results that support a model in which neuronal activity is preferentially fueled by astrocytic lactate. The predicted modulation of endothelial glucose transport by neuronal activity remains to be discovered.