RGE prevents KA-induced neuronal loss in primary cultured hippocampal cells. (a) Concentration data for KA-induced toxicity in primary cultured hippocampal neurons. Examination of the dose effect of KA on neuronal viability by the MTT assay. Neurons were exposed to KA at concentrations of 0, 30, 50, 70, and 100 μ M for 48 h. (b) Protection of hippocampal neurons against KA-induced cell loss by RGE. Neurons were exposed to 100 μ M KA at 1 h after 0.01–1.0 mg/mL of RGE, Trolox (100 μ M), or DMTU (100 μ M) treatment. Cell viability at 48 h after KA exposure was measured by the MTT assay. All data are presented as means ± SE. ### P