Thompson Emily E, Jagielo-Miller Julia E, Vemuri V Kiran, Makriyannis Alexandros, McLaughlin Peter J
Department of Psychology, Edinboro University of Pennsylvania, Edinboro, PA, USA.
Center for Drug Discovery, Northeastern University, Boston, MA, USA.
J Psychopharmacol. 2016 May;30(5):482-91. doi: 10.1177/0269881116639287. Epub 2016 Mar 22.
Cannabinoid CB1 antagonists are widely known to reduce motivation for food, but it is not known whether they induce satiety or reduce reward value of food. It may therefore be necessary to compare effects of altered satiety and reward food value in the same appetitive task, and determine whether CB1 antagonism produces a behavior pattern similar to either, both, or neither. A fine-grained analysis of fixed-ratio 10 (FR10) responding for palatable food initially included number and duration of, and between, all lever presses and food tray entries in order to differentiate the pattern of suppression of prefeeding from that caused by reducing the reward value of the pellets with quinine. Discriminant function analysis then determined that these manipulations were best differentiated by effects on tray entries, pellet retrieval latencies, and time of the first response. At 0.5 mg/kg, AM 6527 produced similar effects to reducing reward value, but at 1.0 and 4.0 mg/kg, effects were more similar to those when animals were satiated. We conclude that AM 6527 both reduced reward value and enhanced satiety, but as dose increased, effects on satiety became much more prominent. These findings contribute to knowledge about the behavioral processes affected by CB1 antagonism.
大麻素CB1拮抗剂能降低对食物的欲望，这一点广为人知，但尚不清楚它们是诱导饱腹感还是降低食物的奖励价值。因此，可能有必要在同一食欲任务中比较改变饱腹感和奖励食物价值的效果，并确定CB1拮抗作用是否会产生与其中一种、两种或都不相似的行为模式。对美味食物进行固定比率10（FR10）反应的精细分析最初包括所有杠杆按压和食物托盘进入的次数、持续时间以及两者之间的间隔，以便区分预喂食抑制模式与用奎宁降低颗粒奖励价值所导致的模式。判别函数分析随后确定，这些操作最好通过对托盘进入、颗粒取回潜伏期和首次反应时间的影响来区分。在0.5毫克/千克时，AM 6527产生的效果与降低奖励价值相似，但在1.0和4.0毫克/千克时，效果更类似于动物处于饱腹状态时的效果。我们得出结论，AM 6527既能降低奖励价值又能增强饱腹感，但随着剂量增加，对饱腹感的影响变得更加显著。这些发现有助于了解受CB1拮抗作用影响的行为过程。
