ABSTRACT
Objective This study aimed at the effect of glutamate(Glu) on rat cortical pyramidal cells in cultured brain slices treated by threohydroxyaspartate(THA),an inhibitor of glutamate transporter.Methods The brain slice cultures were prepared using 1-day-old rat.Various concentrations of THA(50,100 and(500 ?mol/L))were added into the culture medium respectively.Cortical pyramidal cells' survival was evaluated by immunohistochemistry staining monoclonal antibody SMI-32,a nonphosphorylated neurofilament marker,Glu level in the culture medium was also measured.Ultrastructural picture of neuropathology were examined by EM microscopy. Results The brain slices in the control group maintain excellent organization and a stable population of pyramidal cells.THA caused a slow dose-dependent loss of cortical pyramidal cells and an increase of Glu level in the culture medium.THA of 100 ?mol/L resulted in a significant decrease in cortical pyramidal cells after culturing for 5 weeks.Pyramidal cells appeared vacuolar degeneration.Conclu-(sions Extra-cellular) Glu caused chronic excitotoxicity to cortical pyramidal cells.