Fig. 4.

Expression of fosB in the striatum of mice treated with a histone deacetylase inhibitor is enhanced after cocaine treatment. Real-time PCR shows a 3-fold increase in fosB expression after cocaine injection in mice that were pretreated with SAHA. Treatment with SAHA without cocaine administration did not change fosB expression. C57BL/6J were injected with SAHA (25 mg/kg) or vehicle (DMSO) 2 h before receiving cocaine (20 mg/kg). Mice were killed 2 h after the injection of cocaine. n = 18; control set at 1; DMSO and cocaine, 1.25 ± 0.001; SAHA plus cocaine, 3 ± 0.002; ^*, P < 0.05.