Missing pieces to a gloomy jigsaw - glutamate transporters in the depressive state

Half a century after the formulation of the monoamine hypothesis of depression, current pharmacological research in mood disorders focuses mainly on the involvement of the glutamatergic system. Recently, an important role for glial cells in the stressed tripartite synapse was proposed. The cystine/glutamate antiporter or system xc- is responsible for non-vesicular glutamate release from glial cells and glutamate reuptake transporters clear glutamate from the extracellular space into glial cells.