Fig. 4.

Role of glutamate in DA somatodendritic regions. Mean (± SEM) percent of vehicle–saline control (bFGF-immunoreactive cells per square millimeter) in the VTA and SNc in groups of animals treated daily with kynurenic acid (n = 4 per group) or vehicle (VTA,n = 8; SNc, n = 7), given three injections of saline or amphetamine (3.0 mg/kg), and killed 1 week after the last injection of saline or amphetamine;100% represents the mean (solid line) and SEM (dashed lines) counts from vehicle–saline-treated animals (n = 8). See Materials and Methods for details. ANOVAs performed on the actual counts showed significant group difference in each area (VTA, F_(3,20) = 3.77;p < 0.05; SNc,F_(3,19) = 4.11; p < 0.05). Asterisks indicate that the vehicle-amphetamine group was significantly different from all other groups (p < 0.05).