Gerrits M A, van Ree J M
Department of Medical Pharmacology, Rudolf Magnus Institute for Neurosciences, Utrecht University, The Netherlands.
Pharmacol Biochem Behav. 1995 Sep;52(1):35-42. doi: 10.1016/0091-3057(95)00112-a.
A behavioral paradigm was explored to assess the motivational aspects involved in drug-taking behavior during initiation of drug self-administration. In separate saline-controlled experiments, naive animals were allowed to self-administer either cocaine or heroin (0.16 and 0.32 mg/kg per infusion) during five consecutive daily 3-h sessions by pressing one of two levers present in the test cage. During 15 min preceding the last four self-administration sessions, the animals had access to the levers but pressing the reinforcement lever did not result in a drug infusion. The animals properly self-administered both doses of cocaine and heroin, because the amount of self-infusions was higher than their saline control groups. Animals self-administering the high dose of cocaine and either dose of heroin performed lever-press behavior during the preceding period in a similar fashion as during the self-administration sessions, suggesting that this behavior during the preceding period was performed in the absence of the primary reinforcer, this behavior likely reflects the motivational state of animals to obtain the drug reinforcer, and thus may serve as a measure of the motivational aspects involved in the initiation of drug self-administration.
研究了一种行为范式，以评估药物自我给药起始阶段吸毒行为中涉及的动机因素。在单独的生理盐水对照实验中，让未接触过药物的动物在连续5天每天3小时的实验中，通过按压测试笼中两个杠杆之一，自我给药可卡因或海洛因（每次输注0.16和0.32毫克/千克）。在最后四次自我给药实验前的15分钟内，动物可以接触杠杆，但按压强化杠杆不会导致药物输注。动物正确地自我给药了两种剂量的可卡因和海洛因，因为自我给药的次数高于它们的生理盐水对照组。自我给药高剂量可卡因和任一剂量海洛因的动物，在前一阶段的杠杆按压行为与自我给药实验期间相似，这表明在前一阶段的这种行为是在没有主要强化物的情况下进行的，这种行为可能反映了动物获取药物强化物的动机状态，因此可作为药物自我给药起始阶段涉及的动机因素的一种衡量方法。
