5-羟色胺对大鼠脊髓P物质痛觉调制的影响(英文)

Effect of 5-HT on pain modulation of substance P in spinal cord of rats

比较SP,5-HT与For诱发的脊髓内c-fos表达的异同,以及它们之间的相互关系,从而进一步了解SP在脊髓痛觉调制中的主要作用.方法:用免疫组织化学法和痛阈测定法.结果:发现大鼠it P物质(sP)10μg和sc5％甲醛(For)150μL诱发的脊髓c-fos表达主要在背角Ⅰ,Ⅱ,Ⅴ及Ⅵ层,同时SP使痛阈降低,For使痛级均数(PIR)升高.5-HT it 20μg引起的c-fos表达较多地分布于背角Ⅲ—Ⅳ层,并可使痛阈升高.5-HT和Fen可分别减弱和增加SP及For诱发的脊髓c-fos表达及痛反应.结论:SP在脊髓内可能主要起致痛作用,5-HT可抑制SP引起的脊髓c-fos表达,从而参与SP的痛觉调制作用.

To study the effect of serotonin (5-HT) on pain modulation of substance P (SP) in spinal cord of rats. METHODS: Using immunohisto-chemistry and measurement of pain threshold. RESULTS: The c-fos expression evoked by intrathecal injection (it) SP 10μg and sc 5 % formaldehyde (For) 150 μL in the hindpaw was densely distributed in the laminae I ,II , V , and VI of spinal dorsal horn. The pain threshold in the SP group was decreased while the pain intensity rating measured by behavioral method in the For group was increased. The c-fos expression induced by it 5-HT 20μg was mostly distributed in the spinal dorsal horn in laminae I -IV and the pain threshold was increased. SP and For induced c-fos expressions in the spinal cord and the pain responses were reduced by 5-HT and increased by 5-HT deple-tor fenclonine 300 mg.kg-1.CONCLUSION: SP mainly played an algogenesia in the spinal cord. 5-HT inhibited the c-fos expression in the spinal cord evoked by SP and participated in pain modulation of SP.