Microelectrode Arrays Studies of Glutamate Excitatory Pathway in Hippocampus CA3 by Offside KCl and Glutamate Stimulating

Abstract

In our central nervous system (CNS), glutamate is an excitatory neurotransmitter that can be accumulated remarkably by brain tissue. As is noticeable from previous studies, glutamate is somehow closely related with most ways of normal and abnormal cerebral activities. It was significant to monitor glutamate concentration changes in vivo real time. Therefore, we developed an enzyme-based microelectrode array with high sensitivity (7.34pA/µM) and perfect linearity (R2=0.999). Selectivity to normal neurotransmitters satisfied our in vivo demands. Ultimately, we applied the electrode into the brain specific tissue to study glutamate excitatory pathway in hippocampus CA3 by offside KCl and glutamate stimulating. The hippocampus CA3 glutamate was detected about 18.17µM and 13.19µM by twice KCl stimulating in the offside cortex, and 6.50µM, 4.55µM by twice glutamate stimulating. All peak current back to the base level later. The self-regulation ability reflects the glutamate excitatory pathway from hippocampus CA3 to cortex.