牛肾上腺髓质8-22肽增强吗啡的抗伤害作用

Bovine Adrenal Medulla 8-22 Enhances Morphine Antinociception in Rats

采用甩尾反射实验研究椎管内注射感觉神经元特异性受体的激动剂牛肾上腺髓质8-22肽(bovineadrenal medulla 8-22,BAM8-22)对吗啡抗伤害作用的影响.结果表明,BAM8-22本身并不能改变伤害性热刺激引起的甩尾反射潜伏期,但与吗啡混合使用时,能明显增强吗啡的抗伤害作用.0.1,1,10 nmol BAM8-22与0.3μg吗啡混合进行椎管内注射,能剂量依赖地增强吗啡的抗伤害作用.0.1 nmol BAM8-22分别与0.2,1,5μg吗啡混合进行椎管内注射后,吗啡的抗伤害作用分别为35.1%,61.8%,72.7%,明显高于吗啡对照组的13.0%,30.7%,52.8%(P<0.01).本研究表明,BAM8-22能增强吗啡的抗伤害作用,暗示感觉神经元特异性受体(SNSR)参与调制阿片受体的抗伤害过程.

To designed investigate the effect of intrathecal （i. t. ） administration of bovine adrenal medulla 8-22 （BAM8-22）, an agonist of sensory neuron-specific receptors, on the potency of morphine analgesia assessed by tail flick test. It was found that BAM8-22 alone did not alter the tail flick latency, but significantly enhanced the potency of morphine antinociception when the two agents were co-administered. BAM8-22 （0.1, 1, 10 nmol, i. t. ） produced a dose-dependent increase morphine antinoceception when it was co-administed with morphine （0. 3μg）. On the other hand, morphine at the doses of 0.2, 1, 5μg duced 13.0%,30.7% ,52.8 % of maximal possible effects（MPE） but 35.1%,61.8%,72.7% of MpE when it was co-administed with BAM8-22 （0.1 nmol）. These results suggest that sensory neuron-specific receptors （SNSR） exerted a modulation on opioid receptors.