Henck J W, Mokler D J, Commissaris R L, Rech R H
Pharmacol Biochem Behav. 1983 Jan;18(1):41-5. doi: 10.1016/0091-3057(83)90248-4.
Male Sprague-Dawley rats were trained to press a lever on a fixed ratio-40 (FR-40) schedule for food reinforcement. Doses ranging from 0.5 to 16 mg/kg of the mixed narcotic agonist-antagonist cyclazocine (30-min pretreatment) resulted in a dose-dependent decrease in the number of reinforcements obtained and a reciprocal increase in "pausing" (IRT's greater than 10 sec). A 5-min pretreatment with 4 mg/kg of the narcotic antagonist naloxone attenuated the cyclazocine disruption. The 5-HT antagonist metergoline (1 mg/kg; 180-min pretreatment) also blocked cyclazocine effects to approximately the same degree as did naloxone. However, the shift of the dose response pattern of cyclazocine was not parallel for either antagonist. A greater degree of attenuation of the cyclazocine effects was observed when naloxone (4 mg/kg) and metergoline (0.1 mg/kg) were given together, indicating that cyclazocine disruption may be antagonized by either a narcotic antagonist or a 5-HT antagonist, and that these antagonists may operate synergistically. Thus, the behavioral effects of cyclazocine may relate to both opioid and serotonergic components.
雄性斯普拉格-道利大鼠接受训练，在固定比率40（FR-40）的时间表下按压杠杆以获取食物强化。给予0.5至16毫克/千克的混合麻醉激动剂-拮抗剂环唑辛（30分钟预处理），导致获得的强化次数呈剂量依赖性减少，“停顿”（间隔时间大于10秒）相应增加。用4毫克/千克的麻醉拮抗剂纳洛酮进行5分钟预处理可减弱环唑辛的干扰作用。5-羟色胺拮抗剂美替拉酮（1毫克/千克；180分钟预处理）也能阻断环唑辛的作用，其程度与纳洛酮大致相同。然而，两种拮抗剂对环唑辛剂量反应模式的改变并非平行。当同时给予纳洛酮（4毫克/千克）和美替拉酮（0.1毫克/千克）时，观察到环唑辛作用的减弱程度更大，这表明环唑辛的干扰作用可能被麻醉拮抗剂或5-羟色胺拮抗剂拮抗，且这些拮抗剂可能协同作用。因此，环唑辛的行为效应可能与阿片类和5-羟色胺能成分均有关。
