文摘

Background The antinociceptive effect of an aqueous extract from the leaves of Toona sinensis (TS, [A. Juss., M. Roem.]) was studied using the writhing test in mice. Methods Different extraction fractions from TS leaf extracts (TSL1 to TSL5) were administered orally 1?h before intraperitoneal injection of acetic acid. Results After treatment with TSL1, TSL2, TSL3, TSL4, and TSL5 at a dose of 1?g/kg, the respective writhing responses were 39.9% (P--.001), 19.9% (P--.05), 11.7% (P--.052), 8.1% (P--.188), and 11.4% (P--.057) lower than the control group. Mice treated with TSL1 at 1?g/kg (39.9%, P--.001), 0.3?g/kg (38.0%, P--.001), 0.1?g/kg (46.9%, P--.001), and 0.03?g/kg (31.1%, P--.001) had significantly lower writhing responses compared with control mice. A time-course experiment was performed, which involved oral administration of TSL1 (0.1?g/kg) at 0, 0.5, 1, 2, and 6?h before acetic acid intraperitoneal injection. The most effective dose of TSL1 was 0.1?g/kg orally, with the effect beginning 30?min before treatment and persisting until 6?h. Conclusions This study showed that TS has anti-visceral pain properties comparable with those of rofecoxib (a cyclooxygenase-2 inhibitor) and diclofenac, which suggests promise for the treatment of intractable visceral pain in humans.