A, B, Suppression of DNMT3a and DNMT3b expression. RT-PCR assays demonstrated a significant downregulation of DNMT3a (A) and DNMT3b (B) mRNA expression in T7–T10 DRGs in diabetic rats compared with age- and sex-matched CON rats (CON, n = 4, STZ, n = 8, *p < 0.05, **p < 0.01, 2-sample t test). C–E, STZ injection did not alter expression of TDG (C), MBD2 (D), and MBD4 (E) in T7–T10 DRGs compared with age- and sex-matched CON rats (CON, n = 4, STZ, n = 8, p > 0.05, 2-sample t test).