[The high affinity uptake of glutamate in nervous system and its regulation by various factors]

The high affinity uptake of glutamate in nervous system is sodium dependent and is mediated by glutamate transporter proteins located both in the nerve endings which release glutamate as a transmitter and in the plasma membrane of glial cells. Four subtypes (GLUT1, GLAST, EAAC1 and EAAT4) of glutamate transporters have been cloned. The localizations, distributions and pharmacological properties for each of these subtypes are unique from one another. The high affinity uptake of glutamate is regulated by various factors, such as arachidonic acid, nitric oxide, free oxygen radicals, protein kinases, cytokines and growth factors. The regulations are obviously meaningful from the standpoint of physiology and/or pathophysiology.