氯胺酮的镇痛作用与阿片受体的关系

THE RELATIONSHIP BETWEEN ANALGESIC EFFECT OF KETAMINE AND OPIOID RECEPTOR

[目的]探讨氯胺酮的镇痛作用与阿片受体的关系。[方法]120只小鼠随机分成热扳法和扭体法2组。每组再分为2小组:对照组与氯胺酮组。对照组分别腹腔注射生理盐水和不同浓度的纳络酮;氯胺酮组腹腔注射氯胺酮20mg/kg,5min后分别注射生理盐水和不同浓度的纳络酮。在热板、扭体实验中,观察腹腔注射纳络酮对氯胺酮热板法痛阈及扭体次数的影响。[结果]纳络酮对氯胺酮小鼠的扭体次数无显著影响(P﹥0.01),但可减小其热板法的痛阈(P﹤0.01)。[结论]氯胺酮对热刺激的镇痛作用与阿片受体有关,而对化学刺激镇痛作用与阿片受体关系不大。

[Objective] To discuss the relationship between analgesic effects of ketamine and opioid receptor. [Methods] 120 mice were randomly divided into two groups： hot-plate group and writhing test group, and each group was further divided into control group and ketamine group with 10 mice in each subgroup. The control group was treated with intraperitoneal injection of normal saline and different concentrations of naloxone respectively. The ketamine group was treated with intraperitoneal injection of 20 mg/kg ketamine, 5 minutes later, the mice were respectively injected with normal saline and different concentrations of naloxone. The effects of intraperitoneal injection of naloxone on the HPPT （pain threshold in hot plate test） and writhing times were observed. [Results] The intraperitoneal injection of naloxone had no significant effect on the writhing times of the mice injected with ketamine （P〉 0.01）, but could decrease the HPPT （P〈 0.01）. [Conclusions] The analgesic effect of ketamine to thermal stimulation has effect on opioid receptor, while the analgesic effect to chemical stimulation has litde effect on opioid receptor.