Pandolfo Pablo, Vendruscolo Leandro F, Sordi Regina, Takahashi Reinaldo N
Departamento de Farmacologia, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina (UFSC), Florianópolis, SC, Brazil.
Psychopharmacology (Berl). 2009 Aug;205(2):319-26. doi: 10.1007/s00213-009-1542-3. Epub 2009 May 1.
Cannabis preparations are the most widely consumed illicit drugs, and their use typically begins in adolescence. The prevalence of cannabis abuse is higher in patients with attention deficit/hyperactivity disorder (ADHD) than in the general population, yet, knowledge about the motivational properties of cannabinoids in animal models of ADHD are lacking.
To compare the motivational effects of the synthetic cannabinoid agonist WIN55,212-2 (WIN) in adolescent and adult spontaneously hypertensive rats (SHR), a validated animal model of ADHD, and Wistar rats, representing a "normal" genetically heterogeneous population. We also asked whether the effects of WIN depended (1) on the activation of the cerebral subtype of cannabinoid receptors, namely, the CB(1) cannabinoid receptor and (2) on putative changes by WIN in blood pressure.
WIN was tested under an unbiased conditioned place preference (CPP) paradigm. Blood pressure after WIN administration was also monitored in additional groups of rats.
In the Wistar rats, WIN produced place aversion only in the adult but not adolescent rats. In contrast, WIN produced CPP in both adolescent and adult SHR rats. The behavioral effects of WIN were CB(1)-mediated and not related to blood pressure.
The contrasting effects of WIN in Wistar and SHR, and the higher resistance of adolescent rats to the aversive and rewarding effects of WIN in these two strains suggests that both adolescence and the ADHD-like profile exhibited by the SHR strain constitute factors that influence the motivational properties of cannabinoids.
大麻制剂是消费最为广泛的非法药物，其使用通常始于青春期。注意力缺陷多动障碍（ADHD）患者中大麻滥用的患病率高于普通人群，然而，关于大麻素在ADHD动物模型中的动机特性的知识却很缺乏。
比较合成大麻素激动剂WIN55,212-2（WIN）在青春期和成年自发性高血压大鼠（SHR）（一种经过验证的ADHD动物模型）以及代表“正常”遗传异质群体的Wistar大鼠中的动机效应。我们还研究了WIN的效应是否（1）取决于大麻素受体脑亚型即CB(1)大麻素受体的激活，以及（2）取决于WIN引起的血压假定变化。
在无偏倚的条件性位置偏爱（CPP）范式下对WIN进行测试。还在另外几组大鼠中监测WIN给药后的血压。
在Wistar大鼠中，WIN仅在成年大鼠而非青春期大鼠中产生位置厌恶。相比之下，WIN在青春期和成年SHR大鼠中均产生CPP。WIN的行为效应是由CB(1)介导的，且与血压无关。
WIN在Wistar大鼠和SHR大鼠中的不同效应，以及青春期大鼠对WIN在这两种品系中的厌恶和奖赏效应具有更高的抵抗力，表明青春期和SHR品系表现出的类ADHD特征均构成影响大麻素动机特性的因素。
