Figure 4
Long-term effect of binge METH on the levels of ORF-1 mRNA and gDNA in rat brain, liver and muscle.
Adult male Sprague-Dawley rats were administered saline (1 mL/kg) or binge METH (4 × 10 mg/kg, i.p. every 2 h) and sacrificed 7 days after the treatment. Compared with the saline controls, METH significantly increased ORF-1 gDNA levels (A) and decreased ORF-1 mRNA levels (B) in the neurogenic regions of the brain (dentate gyrus and striatum combined) (+71%, **p < 0.01, n = 8–11 and −49%, *p < 0.05, n = 5–7, respectively, Student’s two-tailed t-test). (C) When ORF-1 gDNA was assessed in the striatum, dentate gyrus, liver and muscle, no significant changes were detected using the Student’s t-test with the Bonferroni correction. Data unadjusted for multiple comparisons revealed an increase in ORF-1 gRNA in the dentate gyrus and striatum and a statistical trend for an increase in the liver (+66%, p < 0.05, +76%, p < 0.05 and 2.5-fold, p = 0.064, respectively, Student’s one-tailed t-test). (D) When ORF-1 mRNA was assessed in the striatum, dentate gyrus, liver and muscle (using Student’s t-test with the Bonferroni correction), a significant decrease was observed only in the liver (−91%, *p < 0.0125). Data unadjusted for multiple comparisons revealed a decrease in ORF-1 mRNA in the dentate gyrus and striatum (-41%, p < 0.05 and -57%, p < 0.05, respectively, Student’s one-tailed t-test). The data are expressed as the mean ± SEM. All data were normalized to the saline controls. Abbreviations: d, days; dg, dentate gyrus; gDNA, genomic deoxyribonucleic acid; METH, methamphetamine; mRNA, messenger ribonucleic acid; str, striatum; SAL, saline.
