Barrett R J, Steranka L R
Pharmacol Biochem Behav. 1983 Apr;18(4):611-7. doi: 10.1016/0091-3057(83)90289-7.
Two groups of male Sprague-Dawley rats were trained to discriminate which of two levers to press for milk reinforcement on a VI-20 sec schedule of reinforcement on the basis of whether they were injected intraperitoneally with d-amphetamine (0.50 mg/kg or 1.50 mg/kg) or saline 15 min prior to daily 30 min training sessions. Following acquisition of the discrimination, dose-response functions were generated for both training-dose groups during 5 min test sessions. All subjects were then injected with 1.0 mg/kg of haloperidol for ten consecutive days and retested on either saline or intermediate doses of amphetamine on days 1, 2, 4 and 7 following the final haloperidol injection. The results indicated that chronic haloperidol enhanced the discriminative stimulus properties of amphetamine in both training groups. More importantly, when tested on saline, subjects in both training groups made significantly more responses on the d-amphetamine lever than observed prior to chronic haloperidol. On the basis of linear regression analysis of the dose-response curves it was shown that rats in both groups responded as though they had been injected with 0.18 mg/kg of d-amphetamine. In a second experiment this increase in amphetamine-lever responding when animals were tested with saline following chronic haloperidol was replicated and in addition it was observed that chronic amphetamine had the opposite effect on this measure.
将两组雄性斯普拉格-道利大鼠训练为依据在每日30分钟训练时段前15分钟腹腔注射d-苯丙胺（0.50毫克/千克或1.50毫克/千克）还是生理盐水，按照每20秒一次强化的可变时距强化程序来辨别按压两个杠杆中的哪一个以获取牛奶强化物。在获得辨别能力后，在5分钟的测试时段为两个训练剂量组生成剂量反应函数。然后所有受试动物连续十天注射1.0毫克/千克的氟哌啶醇，并在最后一次氟哌啶醇注射后的第1、2、4和7天用生理盐水或中等剂量的苯丙胺进行重新测试。结果表明，慢性给予氟哌啶醇增强了两个训练组中苯丙胺的辨别性刺激特性。更重要的是，当用生理盐水测试时，两个训练组的受试动物在d-苯丙胺杠杆上做出的反应明显多于慢性给予氟哌啶醇之前观察到的反应。基于剂量反应曲线的线性回归分析表明，两组大鼠的反应就好像它们被注射了0.18毫克/千克的d-苯丙胺。在第二个实验中，重复了动物在慢性给予氟哌啶醇后用生理盐水测试时苯丙胺杠杆反应增加的情况，此外还观察到慢性给予苯丙胺对此指标有相反的作用。
