With this protocol, we propose to test a specific new mechanism that uses diazoxide to chronically increase expression of the glutamate transporter EAAT2, resulting in removal of glutamate from the synaptic cleft. Diazoxide enhances glutamate uptake in glia by activating ATP-sensitive potassium (KATP) channels. We expect that this effect will reduce excessive glutamate transmission and be associated with acute antidepressant effects. The model presented here is a clinically testable one. If successful, it may lead to the development of a group of novel pharmacological treatments for major depressive disorder.