Anxiety-like behavior was tested using the acoustic startle response (ASR) across METH treatments. All animals were injected with 3α,5β-THP (10 mg/kg, i.p.) or oil vehicle 20 min. before testing. A, ASR in vehicle or 3α,5β-THP-injected rats. Mean ± SEM, 2-factor ANOVA, F(7,61)=19.51, P<0.0001; *P<0.05 vs. all other vehicle-treatment groups; †P<0.05 vs. all other 3α,5β-THP -treatment groups; n=9 rats/group. B, 3α,5β-THP effects on the ASR across METH treatment groups. Mean ± SEM, 1-factor ANOVA, F(3,31)=47.7, P<0.0001; *P<0.05 vs. all other groups, n=9 rats/group. 3α,5β-THP increased the startle response only after a 24 h METH Wd (90% of animals), while Flu prevented this effect.