Figure 1.

Effect of valproate on glutamate release from mouse cerebral cortex slices. Slices were prepared, restored, and prelabeled as described in Experimental Procedures. Slices (average protein = 1.5 mg) were washed by incubating four times for 30 min in fresh buffer (3.2 ml). After washing, the slices were preincubated in the absence of Ca²⁺ with the indicated concentrations of sodium valproate for 60 min. The incubations were continued for 20 min with 1.2 mM Ca²⁺. Aliquots of the medium free of slices were analyzed enzymatically for glutamate as described under Experimental Procedures. ³H disintegrations per minute in the medium and tissue were measured, and the values were normalized to total disintegrations per minute to correct for differences in amounts of tissue. This figure combines three separate experiments.