Halford J C, Blundell J E
Department of Psychology, University of Leeds, UK.
Pharmacol Biochem Behav. 1996 Aug;54(4):745-51. doi: 10.1016/0091-3057(95)02228-7.
In this study continuous monitoring was used to yield a true behavioural record. This allows a bidimensional account of drug effects on every unit of behaviour. Behavioural dimensions of duration (dur) and frequency (frq) measures were utilized to monitor the effects of an ED50 anorectic dose of fluoxetine (10 mg/kg i.p.) on the behavioural satiety sequence and the effect of a metergoline (1 mg/kg i.p.) challenge. Fluoxetine reduced food intake by 45% (p < 0.005). The local eating rate was also reduced (p < 0.001), demonstrating a marked slowing of eating behaviour. Eating behaviour was reduced (frq p < 0.05) as was grooming (frq p < 0.05) and activity. Resting was increased (dur p < 0.05) and temporally advanced. There was no gross disruption of behaviour and the profile was adjusted in a way consistent with the expression of satiety. Fluoxetine-induced changes were very similar to those produced by prefeeding. Metergoline antagonised fluoxetine's effect on intake and eating duration (dur p < 0.05). However, metergoline did not antagonise the effect of fluoxetine on the frequency of eating (frq p < 0.005), thus increasing the amount consumed per eating episode. Grooming (frq p < 0.005) and activity also remained reduced. At this dose fluoxetine-induced suppression of eating is serotonin dependent as it is reversed by metergoline. Fluoxetine-induced suppression of eating at this dose is consistent with the normal operation of satiety. Fluoxetine-induced slowing of behavior appears to be mediated by a separate mechanism.
在本研究中，采用连续监测以获取真实的行为记录。这使得能够从二维角度描述药物对每一个行为单元的影响。利用持续时间（dur）和频率（frq）这两个行为维度指标，监测氟西汀（腹腔注射10mg/kg，为半数有效量的厌食剂量）对行为饱腹感序列的影响以及麦角新碱（腹腔注射1mg/kg）激发试验的效果。氟西汀使食物摄入量减少了45%（p<0.005）。局部进食速率也降低了（p<0.001），表明进食行为明显减慢。进食行为减少（frq p<0.05），梳理行为（frq p<0.05）和活动也减少。静息状态增加（dur p<0.05）且时间提前。行为未出现严重紊乱，且行为模式的调整方式与饱腹感的表现一致。氟西汀引起的变化与预喂食所产生的变化非常相似。麦角新碱拮抗了氟西汀对摄入量和进食持续时间的影响（dur p<0.05）。然而，麦角新碱并未拮抗氟西汀对进食频率的影响（frq p<0.005），从而增加了每次进食的摄入量。梳理行为（frq p<0.005）和活动也仍然减少。在此剂量下，氟西汀引起的进食抑制是依赖5-羟色胺的，因为它可被麦角新碱逆转。在此剂量下，氟西汀引起的进食抑制与饱腹感的正常运作一致。氟西汀引起的行为减慢似乎是由一种独立的机制介导的。
