Fig. 2.

The effects of intravenous bicuculline (16 mg/kg, n = 7) and saclofen (16 mg/kg, n = 8) on the antinociception by intravenous sildenafil (30 mg/kg) in spinal nerve ligation-induced neuropathic pain. Bicuculline and saclofen were administered 10 min before the delivery of sildenafil. Data are presented as %MPE. Both bicuculline and saclofen attenuated the antinociception of sildenafil. Neither bicuculline (n = 5) nor saclofen (n = 6) alone affected the control response. Each bar represents mean ± SEM. Compared with sildenafil, ^*p< 0.05, ^†p< 0.01.