Liu X, Strecker R E, Brener J M
Department of Psychology, State University of New York at Stony Brook 11794-2500, USA.
Pharmacol Biochem Behav. 1996 Feb;53(2):335-40. doi: 10.1016/0091-3057(95)02031-4.
The purpose of this study was to examine the effects of low doses of apomorphine on motor performance. Six rats were rewarded with sugar water on a partial reinforcement schedule for pressing force-sensitive beams with a minimum force of 1 g. The kinetics of individual responses and the temporal characteristics of response sequences were measured; open field locomotor activity was also measured in a separate apparatus. Apomorphine (APO), amphetamine (AMP), and haloperidol (HAL) were administered systemically. It was found that low doses of APO (0.03 and 0.1 mg/kg, SC) produced weaker and longer beam presses. These decreases in response peak force resulted from decreases in the rate of rise of force. APO also caused disproportionate lengthening of beam release time. In addition, the low doses of APO increased the time intervals between consecutive components of response sequences. These low doses of APO are known to decrease dopaminergic tone. Hence, the observed pattern of motor dysfunctions produced by APO is similar to the bradykinesia seen in human Parkinson's disease.
本研究的目的是考察低剂量阿扑吗啡对运动表现的影响。六只大鼠在部分强化程序下，因按压最小力为1克的力敏梁而获得糖水奖励。测量了个体反应的动力学和反应序列的时间特征；还在单独的仪器中测量了旷场运动活动。阿扑吗啡（APO）、苯丙胺（AMP）和氟哌啶醇（HAL）经全身给药。结果发现，低剂量的APO（0.03和0.1毫克/千克，皮下注射）会导致较弱且持续时间更长的梁按压。反应峰值力的这些降低是由于力上升速率的降低所致。APO还导致梁释放时间不成比例地延长。此外，低剂量的APO增加了反应序列连续成分之间的时间间隔。已知这些低剂量的APO会降低多巴胺能张力。因此，APO产生的运动功能障碍模式与人类帕金森病中所见的运动迟缓相似。
