桂产藿香蓟乙醇提取物镇痛作用研究

Study on analgesic effects of ethanol extract of Ageratum conyzoides.L. from Guangxi

目的观察桂产藿香蓟乙醇提取物的镇痛作用,探讨其作用机制。方法各自分别取60只合格昆明小鼠,随机分为空白对照组、阿司匹林组(0.4 g/kg)、桂产藿香蓟乙醇提取物高、中、低剂量组,每组各12只。采用热板法、扭体法和甩尾法来观察桂产藿香蓟乙醇提取物的镇痛作用,并测定热板法小鼠血清丙二醛(MDA)、前列腺素E2(PGE2)和超氧化物歧化酶(SOD)的活性。结果①与空白对照组比较,桂产藿香蓟乙醇提取物能显著提高热板法小鼠热刺激痛阈,在给药后30、60、90、120 min均能显著延长小鼠舔足反应的潜伏期,差异均有统计学意义(P<0.05或P<0.01),显著降低小鼠血清MDA和PGE2含量,提高SOD活性,差异有统计学意义(P<0.05或P<0.01)。②与空白对照组比较,桂产藿香蓟乙醇提取物均可显著减少醋酸致痛时小鼠扭体反应的次数,差异有统计学意义(P<0.05或P<0.01),其中桂产藿香蓟乙醇提取物高、中和低剂量组(6.0、3.0、1.5 g/kg)扭体抑制率分别为45.45%、35.65%和15.66%。③无论是与空白对照组比较还是与本组给药前比较,桂产藿香蓟乙醇提取物在给药后30、60、90、120 min能显著延长小鼠甩尾反应潜伏期,差异有统计学意义(P<0.05或P<0.01)。结论桂产藿香蓟乙醇提取物具有显著的镇痛作用,其机制之一可能与减少炎症介质释放、清除氧自由基有关。

Objective To observe analgesic effects of ethanol extract of Ageratum conyzoides.L.from Guangxi and to explore its analgesic mechanisms.Methods 60 Kunming mice were selected individually in hot-plate method,bodytorsion method and swinging-tail method,all of them were divided into blank control group,Aspirin group （0.4 g/kg）,Ageratum conyzoides.L.low dosage group,medium dosage group,high dosage group with 12 rats in each group.Hot-plate method,body-torsion method and swinging-tail method were used respectively to investigate the analgesic effects of ethanol extract of Ageratum conyzoides.L.from Guangxi,and then,the contents of malondialdehyde （MAD） and prostaglandin E2 （PGE2） and the activity of superoxide dismutase （SOD） in hot-plate mice serum were measured.Results ①Compared with blank control group,thermal stimulation threshold in hot-plate mice was enhanced by the ethanol extract of Ageratum conyzoides.L.from Guangxi,the latency time of the mice＇s licking at 30,60,90,120 min respectively were prolonged,the differences were statistically significant（P 〈 0.05 or P 〈 0.01）.Meanwhile,MDA and PGE2 productions were reduced and SOD level in mice serum enhanced,the differences were statistically significant （P 〈 0.05 or P 〈 0.01）.②Compared with model control group,mouse twisting munbers were remarkably reduced by Ageratum conyzoides.L.from Guangxi,the differences were statistically significant （P 〈 0.05 or P 〈 0.01）.Body twisting inhibition rate in high,medium and low dosage group （6.0,3.0,1.5 g/kg） were 45.45%,35.65% and 15.66% respectively.③Not only compared with blank control group but also compared with former dose in each group,the latency of the tail flick response in the mice at 30,60,90,120 min were prolonged respectively after given the ethanol extract of Ageratum conyzoides.L.from Guangxi,the differences were statistically significant （P 〈 0.05 or P 〈 0.01）.Conclusion The ethanol extract of Ageratum conyzoides.L.from Guangxi has significantly analgesic effects,one of its analgesic mechanisms may be relate to its ability of scavenging oxygen free radicals and reducing the release of inflammatory cytokines.