Fig. 2. Time course of d-aspartate efflux from astrocytes exposed to organic peroxide and propofol seriatim. Astrocytes were preloaded with d-[3H]aspartate (10 μm) overnight. Subsequently, beginning at time zero of efflux, they were incubated with tert-butyl hydroperoxide (t-BOOH; 1 mm) or aqueous vehicle for 30 min, followed by incubation with propofol (1 μm) or Intralipid vehicle for an additional 90-min period (37°C). Cumulative d-aspartate efflux rates are expressed as percentages of the d-aspartate present in the cells initially. Plotted are the mean ± SD values for seven experiments with triplicate determinations in each. * P less than 0.05 compared with vehicle control that did not receive t-BOOH.