【摘要】 目的　在体探讨脊髓去甲肾上腺素 (NE)能神经元α1受体和氯胺酮 (Ket)脊髓镇痛的关系。方法　用热水甩尾法观察鞘内注射 (ith)氯胺酮 5 0、10 0、2 0 0 μg对小鼠甩尾潜伏期(TFL)的影响。并观察鞘内分别预先注射 6 羟多巴胺 (6 OH DA ,6 μg)、α1受体拮抗剂哌唑嗪 (Pra,5、15 μg)或特拉唑嗪(Ter,5、15 μg )对Ket(10 0 μg ,ith)脊髓镇痛的影响。 结果　Ket(5 0 μg ,ith)对小鼠TFL无影响 (P >0 0 5 ) ,而Ket(10 0、2 0 0μg ,ith)可剂量依赖性地延长小鼠TFL(P <0 0 5 )。鞘内单独注射 6 OHDA、Pra或Ter对小鼠的痛阈无影响 (P >0 0 5 )。ith 5 μgPra或Ter对Ket脊髓镇痛无影响 (P >0 0 5 ) ,而ith 6 OHDA、15 μgPra或Ter则可明显减弱Ket脊髓镇痛 (P <0 0 5 )。结论　脊髓是Ket的镇痛部位之一 ,Ket脊髓镇痛和脊髓NE神经元α1受体有关更多还原

【Abstract】 Aim To investigate the relationship between spinal cord noradrenergic neurons α 1 adrenoceptors and the spinal analgesia of ketamine. Methods Kunming mice were used. Analgesia tests were investigated with warm water tail flick test. The effects of intrathecal injection (ith) of ketamine (50,100,200 μg)on tail flick latency of animals were observed. And the effect of pretreatment with intrathecal 6 hydrodoapa(6 OHDA, 6μg ) and α 1 adrenoceptor antagonist prazosin (5, 15 μg) or terazosin (5, 15 μg) , respectively on the spinal analgesia of ketamine (100 μg,ith) was studied. Results Dose dependent analgesia was observed following ith ketamine (100,200 μg, P <0 05). Intrathecal 6 OHDA, prazosin or terzosin alone did not affect basal tail flick latency. Pretreatment with intrathecal 5 μg prazosin or terzosin had no effect on the spinal analgesia of ketamine, but pretreatment with intrathecal 6 OHDA , 15 μg prazosin or terazosin significantly reduced the spinal analgesia of ith ketamine but not 5 μg ( P <0 05). Conclusion Spinal cord is one of the targets of ketamine analgesia. The spinal analgesia of ketamine is partly mediated by spinal noradrenregic neurons and α 1 adrenoceptors.更多还原