苦参碱的镇痛作用部位及机制研究

目的:研究苦参碱的镇痛作用部位及机制.方法:采用小鼠醋酸扭体法,观察用后扭体反应数,舔小足潜期及组织NO含量的变化.结果:苦参碱侧脑室注射(icv)0.25,0.5nm/kg,ip或iv3.75,7.5,15,30mg/kg均可显著减少小鼠扭体反应数,并呈量效关系;ip与iv同等剂量的苦参碱,对小扭体反应的抑制欧以iv为强,给药后各时段的ip抗扭体半数有数量(ED50)均大于iv抗扭体ED50,ip苦参碱7.5,30mg/kg可显著降低醋酸致痛小鼠脑组织NO含量,进一步研究发现苦碱延长小鼠舔小足潜伏期的作用可被沦钙所拮抗,而被维拉帕米所增强.结论:苦参碱的镇痛作用部位在中枢,其镇痛作用可能与影响Ｃa^2 内流和减少ＮＯ生成有关.

Studies on site of analgesic action of matrine and its mechanism

Object The site of analgesic action of matrine (Ma) and its mechanism were studied Methods Adopting acetic acid writhing and hot plate test in mice, the changes of the number of writhing, the latencies of paw licking and the content of nitric oxide (NO) in the brain tissue after administration were recorded Results Ma (0 25, 0 5 mg/kg, icv; 3 75, 7 5, 15, 30 mg/kg, ip or iv) could remarkably and dose dependently reduce the numbers of writhing When the same doses of Ma were given by ip and iv, its inhibitory effect on mouse writhing was more pronounced by iv than that by ip The anti writhing ED 50 of Ma at any time after ip was larger than that after iv Ma (7 5, 30 mg/kg, ip) could also obviously lowered the content of NO in the brain tissue of acetic acid writhing mouse It was further found that the action of Ma that prolonged the latencies of paw licking could be antagonized by CaCl 2 and enhanced by verapamil Conclusion The site of analgesic action of Ma is located in the central nervous system Its mechanism of analgesic action may be related to its influence on the transmembrane influx of Ca 2 and reducing the output of NO