Figure 3.

METH induced expression of shati mRNA in the brain. A, Dose-dependent effect of repeated METH treatment on shati mRNA expression in the NAc. Mice were administered METH (0.3, 1, and 2 mg/kg, s.c.) for 3 d. Mice were decapitated 2 h after the last METH treatment. Values are means ± SE (n = 8). *p < 0.05 versus saline-treated mice. B, Time course changes in the expression of shati mRNA after repeated METH treatment in the NAc. Mice were administered METH (2 mg/kg, s.c.) for 6 d and decapitated 1, 2, 6, 24, and 48 h and 1 week after the last METH treatment. Values are means ± SE (n = 6–7). *p < 0.05 versus saline-treated mice. C, Changes in the expression of shati mRNA in the various brain regions (Fc, NAc, CPu, and Hip) of the mice after single and repeated METH treatment. Mice were administered METH (2 mg/kg, s.c.) for 5 d and challenged with METH (2 mg/kg, s.c.) or saline on day 6. Mice were decapitated 2 h after last treatment of METH (2 mg/kg, s.c.) or saline challenge. Values are means ± SE (n = 8–10). *p < 0.05 versus saline-treated mice. D, The effects of the DA D₁-like receptor antagonist R(+)-SCH23390 or D₂-like receptor antagonist raclopride on METH-induced expression of shati mRNA in the NAc. Mice were treated with R(+)-SCH23390 (0.1 mg/kg, s.c.) or raclopride (2 mg/kg, s.c.) 30 min before daily METH (2 mg/kg, s.c. for 6 d) treatment. Mice were decapitated 2 h after the last METH treatment. Values are means ± SE (n = 6–8). *p < 0.05 versus vehicle/saline-treated mice. ^#p < 0.05 versus vehicle/METH-treated mice.