Kamien J B, Woolverton W L
Psychopharmacology (Berl). 1985;87(3):368-70. doi: 10.1007/BF00432723.
Rats (N = 11) were trained to discriminate SKF 38393 (8.0 mg/kg, IP), a D1 dopamine receptor agonist, from saline in a two-lever, food-reinforced (FR 30) drug discrimination paradigm. The discrimination was acquired by nine rats within an average of 77 +/- 6 (SEM) sessions. Subsequently, various doses of SKF 38393 as well as SKF 82526, a potent, selective D1 agonist that does not readily penetrate the blood-brain barrier, were injected prior to test sessions. SKF 38393 (2-16 mg/kg) produced a dose-related increase in the percent of responses that occurred on the drug lever during test sessions. On the other hand, SKF 82526 (0.125 and 1.0 mg/kg) induced no drug-appropriate responding. This experiment establishes that SKF 38393 can serve as a discriminative stimulus in rats. Furthermore, the observation that SKF 82526 did not substitute for SKF 38393 in this paradigm makes it unlikely that this effect involves a peripheral site of action. The results suggest the existence of a functional, behaviorally relevant D1 dopamine receptor in the CNS of rats.
将11只大鼠训练至能在双杠杆、食物强化（固定比率30）的药物辨别范式中区分SKF 38393（8.0毫克/千克，腹腔注射），一种D1多巴胺受体激动剂，与生理盐水。9只大鼠在平均77±6（标准误）次实验中习得这种辨别能力。随后，在测试实验前注射不同剂量的SKF 38393以及SKF 82526，一种不易穿透血脑屏障的强效、选择性D1激动剂。SKF 38393（2 - 16毫克/千克）在测试实验期间使药物杠杆上出现的反应百分比呈剂量相关增加。另一方面，SKF 82526（0.125和1.0毫克/千克）未诱发与药物相符的反应。该实验证实SKF 38393可在大鼠中作为辨别性刺激物。此外，在该范式中SKF 82526不能替代SKF 38393这一观察结果表明，这种效应不太可能涉及外周作用部位。结果提示大鼠中枢神经系统中存在功能性的、与行为相关的D1多巴胺受体。
