Dall'Olio R, Gandolfi O, Vaccheri A, Roncada P, Montanaro N
Institute of Pharmacology, University of Bologna, Italy.
Psychopharmacology (Berl). 1988;95(3):381-5. doi: 10.1007/BF00181952.
The selective D1 receptor stimulant SKF 38393 dose-dependently increased grooming time in rats without affecting locomotor activity or eliciting stereotyped behaviour. The selective D2 receptor agonist LY 171555 induced a dose-dependent increase in rat motility, a marked decrease in grooming time and a low occurrence of stereotyped behaviour. Concurrent administration of the two selective agonists induced high-degree stereotyped responses and reductions in locomotor and grooming behaviours. Rats withdrawn from repeated treatment with the selective D1 receptor blocker SCH 23390 (0.05 mg/kg twice daily for 21 days; 7 days of washout) did not exhibit any change of locomotor and grooming responses to threshold doses of LY 171555 and SKF 38393 given alone or in combination. On the contrary, a significantly greater occurrence of high-degree stereotyped responses to the combination of the two selective agonists was observed. The data support the view that D1 and D2 receptors have a cooperative role in the generation of stereotypies and suggest that D1 receptor supersensitivity needs D2 stimulation to be revealed.
选择性D1受体激动剂SKF 38393可使大鼠理毛时间呈剂量依赖性增加，而不影响其运动活性或引发刻板行为。选择性D2受体激动剂LY 171555可使大鼠运动性呈剂量依赖性增加，理毛时间显著减少，且刻板行为发生率较低。同时给予这两种选择性激动剂会引发高度刻板反应，并减少运动和理毛行为。用选择性D1受体阻滞剂SCH 23390重复治疗（0.05毫克/千克，每日两次，共21天；洗脱7天）后停药的大鼠，对单独或联合给予的阈剂量LY 171555和SKF 38393的运动和理毛反应均未表现出任何变化。相反，观察到对两种选择性激动剂组合出现高度刻板反应的发生率显著更高。这些数据支持了D1和D2受体在刻板行为产生中具有协同作用的观点，并表明D1受体超敏反应需要D2刺激才能显现出来。
