Fig. 4.

Effect of METH (30 mg/kg, s.c.) on extracellular striatal DA and indices of free radical formation. A, Microdialysis was used to measure extracellular monoamine levels in freely moving mice as described in Materials and Methods. The data are expressed as percentage of average values of at least three basal values before drug administration, each mouse used as its own control. Means ± SEM are shown (n = 5–7). All points representing the effect of METH in both wild-type and VMAT2+/− mice were significantly different (p < 0.05) from saline-treated controls (data not shown). *p < 0.05 versus VMAT2+/− mice.B, C, Effect of METH on the in vivo indices of hydroxyl radical formation in the striatum. 2,3-DHBA (B) and 2,5-DHBA (C) dialysate concentrations were measured during infusion of 5 mm salicylate into the striatum of freely moving mice as described in Materials and Methods. Values represent the mean ± SEM of four to six experiments. *p < 0.05 versus VMAT2+/− mice.