Liles J H, Flecknell P A, Roughan J, Cruz-Madorran I
Comparative Biology Centre, Medical School, University of Newcastle upon Tyne, UK.
Lab Anim. 1998 Apr;32(2):149-61. doi: 10.1258/002367798780600025.
The effects of oral administration of buprenorphine ('buprenorphine jello'), a partial mu opioid agonist, oral naltrexone, a mu antagonist and morphine, a mu agonist, were investigated in rats following laparotomy. Food and water consumption and body weight were reduced in rats that underwent surgery. Rats undergoing anaesthesia alone showed only a small reduction in water consumption. Administration of oral buprenorphine (0.5 mg/kg in flavoured gelatin) decreased the effects of surgery on body weight and water intake when compared to untreated (vehicle alone) controls. The magnitude of this beneficial effect was similar to that seen in previous studies using subcutaneous administration of buprenorphine. The fall in body weight and food and water intake following surgery was similar in the groups which received morphine and the control group which received vehicle (jelly). Neither the magnitude of the fall in body weight, and food and water intake, nor the behavioural scores differed between naltrexone and control (vehicle alone) rats following surgery. This suggests that the beneficial effects of partial agonist analgesics are mediated by a reduction in pain rather than by antagonism of endogenous opioids. Both anaesthesia and surgery caused changes in behaviour, but the major effects of buprenorphine in normal (unoperated) rats severely limited the value of behavioural parameters as a means of assessing possible beneficial effects of analgesic administration.
在大鼠剖腹术后，研究了口服丁丙诺啡（“丁丙诺啡果冻”）（一种μ阿片受体部分激动剂）、口服纳曲酮（一种μ阿片受体拮抗剂）和吗啡（一种μ阿片受体激动剂）的效果。接受手术的大鼠的食物和水消耗量以及体重均下降。仅接受麻醉的大鼠水消耗量仅有小幅下降。与未治疗（仅给予赋形剂）的对照组相比，口服丁丙诺啡（0.5毫克/千克，溶于调味明胶中）减轻了手术对体重和水摄入量的影响。这种有益效果的程度与先前使用皮下注射丁丙诺啡的研究中所见相似。接受吗啡的组和接受赋形剂（果冻）的对照组术后体重、食物和水摄入量的下降情况相似。术后纳曲酮组和对照组（仅给予赋形剂）大鼠在体重、食物和水摄入量下降的幅度以及行为评分方面均无差异。这表明部分激动剂镇痛药的有益效果是通过减轻疼痛而非拮抗内源性阿片类物质来介导的。麻醉和手术均导致行为改变，但丁丙诺啡对正常（未手术）大鼠的主要影响严重限制了行为参数作为评估镇痛药给药可能有益效果手段的价值。
