Administration of DAPT after appearance of pain sensitivity significantly reverses the mechanical allodynia in SNI-induced neuropathic pain. (A) DAPT (50 μM, 10 μL) or DMSO was once administrated after appearance of mechanical allodynia induced by SNI. The mechanical PWT was measured before SNI operation (baseline), before (0 h) as well as 3 h, 6 h, 12 h, 24 h, 36 h, 48 h, 72 h and 96 h after DAPT or DMSO administration. The data represent mean ± SD (n = 6 per group). *P < 0.05 versus SNI group. (B) Different doses of DAPT (25, 50 and 100 μM) or DMSO were administered after the appearance of mechanical allodynia. Mechanical PWT was measured prior to SNI surgery (BL), prior to administration (0 h) and 24 h following DAPT or DMSO administration. The data represent mean ± SD (n = 6 per group). *P < 0.05 versus DMSO group; †P < 0.05 versus DAPT 25 μM group; ‡P < 0.05 versus DAPT 100 μM group. SNI: spared nerve injury; BL: baseline; g: gram; d: day, h: hour.