不同剂量五味子多糖灌胃给药镇痛作用的观察

Observation of analgesic effects of intragastric fructus schizandrae polysaccharide administration at different doses

目的:研究不同剂量五味子多糖灌胃给药对小鼠酒石酸锑钾扭体反应和大鼠甲醛致痛行为的抑制作用.方法:将50只小鼠随机分为生理盐水组,阿司匹林组(100mg/kg)和五味子多糖20,50和100 mg/kg不同浓度组.将50只大鼠随机分为生理盐水组,阿司匹林(100 mg/kg)组,五味子多糖20,50和100 mg/kg不同浓度组.五味子多糖采取灌胃给药,连续给药7 d,于第8日给药后进行痛行为学检测.分别给予小鼠腹腔注射0.2,0.5 mL/L酒石酸锑钾后观察并记录10 min的扭体次数.大鼠左后足底掌侧皮下注射20 g/L甲醛50μL后,立即放入20 cm×20 cm×25 cm的树脂玻璃箱中,记录大鼠60 min内每5 min出现自发缩足、舔足的持续时间.以缩足和舔足时间之和作为伤害性反应的行为学指标.结果:五味子多糖灌胃给药对于小鼠的扭体反应具有显著的抑制作用,且呈一定的剂量依赖性,剂量20,50和100 mg/kg下的扭体次数分别为(27.80±5.81)次,(24.90±3.75)次和(15.30±3.43)次,与对照组(32.90±7.40)次相比较,差异具有统计学意义(P<0.05).50和100 mg/kg五味子多糖可显著降低甲醛第一时相和第二时相的伤害性反应表达,而20mg/kg五味子多糖对甲醛疼痛双相反应无抑制作用.结论:五味子多糖灌胃给药对于小鼠扭体试验和大鼠甲醛试验两种不同性质的病理性痛都有镇痛作用.

AIM： To investigate the inhibitory effects of intragastric fructus schizandrae polysaccharide administration at different doses on mouse potassium antimony tartrate-induced writhing response and rat formalin-induced pain behavior. METHODS： Fifty mice were randomly distributed into： saline group, aspirin 100 mg/kg group, fructus schizandrae polysaccharide 20 mg/kg group, 50 mg/kg group and 100 mg/kg group. Fifty rats were randomly distributed into： saline group, aspirin 100 mg/kg group, fruetus sehizandrae polysaeeharide 20 mg/kg group, 50 mg/kg group and 100 mg/kg group. After continuous intragastrie administration of fruetus sehizandrae polysaeeharide for 7 d, the pain behavior examinations were conducted on day 8. The mice, after intraperitoneal injection of 0.2 mL 0.5 mL/L potassium antimony tartrate, were placed under observation and the writhing times within 10 min were recorded. The rats, after subcutaneous injection of 50 μL 20 g/L formalin under the plantar surface of the left hind paw, were placed in 20 cm × 20 cm × 25 cm Plexiglas box and the spontaneous flinching and licking durations during each 5 min were recorded for 60 rain time course. The durations of flinch and licking were set as the behavior indexes for nocicep- tire response. RESULTS： Intragastric administration of fructus schizandrae polysaccharide produced significant inhibition on mouse writhing response in a dose-dependent manner. Tile writ- hing times at the doses of 20, 50 and 100 mg/kg were 27.80± 5.81, 24.90 ± 3.75 and 15.30 ± 3.43, respectively, with statistical significance when companed with that of the saline group （ 32.90 ± 7.40）. Fructus schizandrae polysaccharide administration at relatively higher dose（50 and 100 mg/kg）sigrfificantly decreased the nociceptive response expression of phase 1 and phase 2 in formalin test, while fructus schizandrae polysaccharide administration at low dose （20 mg/kg） showed no inhibitory effect on the two phase responses induced by formalin injection. CONCLUSION： Intragastric administration of fructus schizandrae polysaccharide presents significant inhibition on pathological pain of different natures in mouse writhing test and rat formalin test.