脊髓5-HT_3受体激活对大鼠伤害性行为的双向调节作用  

Bidirectional Modulation of Nociceptive Behavior by the Activation of Spinal 5-HT_3 Receptors in Rats

作　　者：化伟[1] 闫秋丽[1] 罗丽丹[1] 李应续[2] 

机构地区：[1]武汉大学基础医学院,研究生湖北武汉430071 [2]咸宁学院基础医学院解剖学教研室

出　　处：《咸宁学院学报（医学版）》2011年第1期1-4,共4页Journal of Xianning Univarsity(medical Sciences)

基　　金：湖北省教育厅科学技术研究项目资助(Q200528001)

摘　　要：目的探讨脊髓5-HT3受体对大鼠伤害性行为反应的影响。方法采用鞘内给予受体特异性激动剂和拮抗剂,观察动物给药前后对辐射热产生缩爪反应潜伏期(HWL)的变化。结果鞘内注射5-HT3受体特异性激动剂2-甲基-5-羟色氨(2-m-5-HT),浓度依赖性地延长HWL,该延长作用可被5-HT3受体拮抗剂ICS205930完全阻断;鞘内单独注射GABAA受体拮抗剂荷包牡丹碱(Bic)对动物的HWL无显著影响(P>0.05),但Bic和2-m-5-HT共同注射后,2-m-5-HT对HWL的延长作用不仅完全被阻断,而且动物的HWL较注射前显著缩短(P<0.05),该缩短作用也可被ICS20593完全阻断。结论脊髓5-HT3受体对伤害性信息具有双向调节作用,经GABAA受体介导抗伤害性效应,阻断GABAA受体后,激活5-HT3受体产生痛觉易化。Objective To further explore the effect of spinal 5-HT3 receptors on nociceptive behavior in rats. Methods The latency of hindpaw withdrawal（HWL） induced by thermal stimulation was measured after intrathecal injection of the specific 5-HT3 receptor agonist and antagonist. Results Intrathecal injection of 2-methyl-5-HT,a specific 5-HT3 receptor agonist,dose dependently prolonged HWL.The prolonged effect of 2-methyl-5-HT on HWL could be blocked completely by ICS205930,a selective 5-HT3 receptor antagonist.HWL did not change evidently by intrathecal administration of bicuculline alone,a GABAA receptor antagonist（P0.05）.After co-injection of 2-methyl-5-HT with bicuculline,not only the prolonged effect of 2-methyl-5-HT on HWL was blocked completely,but also HWL shorten significantly compared with HWL before injection（P0.05）.The shortened effect of co-injection of 2-methyl-5-HT with bicuculline on HWL could be also blocked completely by ICS205930. Conclusion 5-HT3 receptor can exert a bidirectional modulation on nociceptive processing in the spinal cord,that has antinociceptive effect via GABAA receptor and facilitation of nociception after the blockade of GABAA receptor.

关 键 词：5-HT3受体 伤害性行为 调节 脊髓 

分 类 号：R338[医药卫生—人体生理学]