Papasava M, Singer G, Papasava C L
Pharmacol Biochem Behav. 1986 Sep;25(3):623-7. doi: 10.1016/0091-3057(86)90151-6.
The objectives in these experiments were to determine the effects on intravenous phentermine self-administration of abrupt refeeding and of saline substitution in food-deprived rats. In Experiment 1, 32 naive rats, reduced to 80% free-feeding weight (FFW), were assigned randomly to four equal-sized groups. Two groups self-administered phentermine, the other two saline over two consecutive six-day phases. In phase 1, all animals were maintained at 80% FFW, while in phase 2, one phentermine- and one saline-reinforced group was abruptly food satiated. Results showed that phentermine self-administration was suppressed. In Experiment 2, another 32 naive rats were assigned to four equal-sized groups and tested over two consecutive six-day phases. Two groups were FF, the other two were reduced to 80% FFW. In phase 1, a group of FF and 80% FFW animals self-administered phentermine, the other two saline, while in phase 2, treatments were reversed: previously phentermine-reinforced animals self-administered saline and vice versa. Findings showed that 80% FFW rats rapidly discriminate the introduction or removal of phentermine and alter responding accordingly, while FF animals respond at low rates throughout.
这些实验的目的是确定在食物剥夺的大鼠中突然重新喂食和用生理盐水替代对静脉注射苯丁胺自我给药的影响。在实验1中，将32只未经处理的大鼠体重降至自由进食体重（FFW）的80%，随机分为四个大小相等的组。两组大鼠自我注射苯丁胺，另外两组注射生理盐水，连续进行两个六天的阶段。在第1阶段，所有动物维持在80%FFW的体重，而在第2阶段，一个苯丁胺强化组和一个生理盐水强化组突然给予充足食物。结果显示苯丁胺自我给药受到抑制。在实验2中，另外32只未经处理的大鼠被分为四个大小相等的组，并连续进行两个六天的阶段测试。两组大鼠自由进食，另外两组体重降至80%FFW。在第1阶段，一组自由进食和80%FFW的动物自我注射苯丁胺，另外两组注射生理盐水，而在第2阶段，处理方式颠倒：先前用苯丁胺强化的动物自我注射生理盐水，反之亦然。研究结果表明，体重为80%FFW的大鼠能迅速辨别苯丁胺的引入或去除，并相应地改变反应，而自由进食的动物在整个过程中的反应率较低。
