Figure 4.
B6D2F2 mice exhibit a conditioned place preference (CPP) to a low, but not to higher, doses of methamphetamine (MA). Data for the 30-min drug-free preference test in mice conditioned with MA on the grid (G+) or on the hole (G-) floor were analyzed as: (A) sec/min on the grid floor for each group (n = 15-17 per group and dose), and (B) percent time on the MA-paired floor for the two groups combined (n = 31-32 per dose). Bars and error bars are means ± SEM. ***p<.001 for the comparison of G+ and G- at 0.5 mg/kg MA. *p<.05 for the comparison between 0.5 mg/kg MA and either 1.0 or 2.0 mg/kg MA.