Fig. 1. Time-dependent induction of cell death of CGNs (A) or cortical neurons (B) by ß-BTx, notexin, taipoxin and textilotoxin. Neurons were incubated for the indicated times with 5 nM of each toxin, washed extensively and further incubated for 4 hours in the presence of resazurin to quantify the mitochondrial activity of viable cells. Values are averages of three independent experiments with triplicate measurements; error bars indicate s.d.