Measuring the effect of glutamate receptor agonists on extracellular d-serine concentrations in the rat striatum using online microdialysis-capillary electrophoresis

Online microdialysis-capillary electrophoresis (CE) was used to measure the changes in extracellular d-serine concentration in response to the application of glutamate agonists and antagonists in the rat striatum. The microdialysis-CE assay was capable of measuring concentration changes as small as 8% with a sampling rate of 12-15 s. Kainic acid (KA) induced increases in d- and l-serine concentrations. Application of the non-NMDA receptor antagonist CNQX did not affect the increases observed for d- or l-serine, suggesting a nonspecific effect. NMDA also induced increases in d-serine, l-serine, glutamate and GABA concentrations. These increases were attenuated by the NMDA receptor antagonist MK-801.