Fig. 7.

Susceptibility of neurons from single or combined mutants to glutamate excitotoxicity. Cortical neurons from single mutants, heterozygotes, or double mutants showed no difference in their resistance to glutamate toxicity compared to wt neurons. Primary cortical neurons of the indicated genotypes were cultivated for 15 d before they were treated with glutamate, and their survival was analyzed by MTT assays. A, B, Cultures were exposed to different glutamate concentrations (10, 25, 50, 100 μm) for 24 hr. C, D,Glutamate (50 μm) was applied for 1 and 3 hr. MTT measurements were performed immediately after the glutamate exposures. Neurons from embryos of the respective genotypes were generated as described in Materials and Methods.