中枢神经系统一氧化氮对大鼠的痛觉调制作用

以钾离子透入引起大鼠甩尾的电流强度（ｍＡ）作为痛反应指标，采用侧脑室微量注射Ｌ－精氨酸（Ｌ－Ａｒｇ）、亚甲基蓝（ＭＢ）等，大鼠痛阈的变化，分析探讨中枢神经系统中一氧化氮（ＮＯ）对大鼠痛觉的调制作用，结果显示：大鼠侧脑室微量注射ＮＯ前体及供体物质Ｌ－Ａｒｇ和硝普钠（ＳＮＰ）均引起明显的痛敏效应。微量注射ＭＢ和Ｌ－ＮＡＭＥ后大鼠痛阈升高非常显著。侧脑室微量注射ＭＢ和Ｌ－Ａｒｇ混合液后，大鼠痛阈较单纯注

The effect of nitric oxide on modulation of pain in central nervous system of rats

The potassium inotophoresis induced tail flick was used to measure the pain threshold(PT) of rats. The changes of PT were investigated by microinjecting L arginine( L Arg) and methylene blue(MB) et al into cerebral ventricular of rats. The significant hyperalgesic effects were observed by injecting L Arg and sodium nitroprusside (SNP) into cerebral ventricular of rats. The PT of rats was increased significantly by microinjecting MB and N G nitro L arginine methyl ester( L NAME) into ventricular of brain. When the MB plus L Arg mixed liquid (MB L Arg group) was injected into cerebral ventricular of rats,the PT of rats was decreased compared with that of MB group,but it was increased more than that of L Arg group. These results suggested that an increase of NO in brain produce hyperalgesia,and a decrease of NO level produce analgesia. The effects of nitric oxide on modulation of pain in central nervous system of rats may be partially mediated by NO cyclic GMP pathway.