A quantitative analysis of glutamate in brain dialysate was made by using an enzymatic cycling technique. This method made it possible to measure the concentration of glutamate in dialysate collected at 30-s intervals. Dialysates were collected from Mongolian gerbil hippocampus before, during, and after two 90-s ischemic insults at an interval of 5 min. An extracellular increase in levels of glutamate was already observed in samples collected during a 30-60 s period after the onset of each ischemia, and the levels of glutamate were maximal at the end of each period of ischemia (approximately a fourfold increase). The increased levels of glutamate rapidly returned almost to preischemic levels by 30 s of recirculation. This method will provide more precise information about temporal changes in the extracellular glutamate concentration in the brain during ischemia.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.