Behavioral and Cellular Neuroscience, Department of Psychology, Texas A&M University, College Station, TX 77843, USA.
Addict Biol. 2013 Mar;18(2):274-85. doi: 10.1111/j.1369-1600.2011.00426.x. Epub 2012 Feb 17.
Social/peer influences are among the strongest predictors of adolescent drug use. However, this important subject does not get much attention in pre-clinical studies. We recently observed that exposure to different social partners modulates morphine locomotor sensitization. Sensitivity to the hyper-locomotor response of drugs of abuse is a predictor of sensitivity to other drug-induced behaviors. Thus, this study examined how exposure to different social partners affected the rewarding properties of morphine. All animals were group-housed four per cage in one of two conditions referred to as 'only' and 'cage-mates'. In the mixed treatment condition, morphine- and saline-treated mice were housed together. These groups are referred to as 'morphine cage-mates' and 'saline cage-mates', respectively. In the separated treatment conditions, all mice in the cage received morphine (i.e. 'morphine only') or saline (i.e. 'saline only'), and cages were visually separated from each other. All animals were subsequently individually tested for the acquisition of morphine conditioned place preference (CPP) following one conditioning session with 10, 20 or 40 mg/kg morphine or saline. As expected, one conditioning session established morphine CPP in the morphine only animals, but not in the saline only animals. Notably, morphine CPP was not acquired by the morphine cage-mate animals. Additionally, 40 mg/kg morphine was sufficient to establish morphine CPP in the saline cage-mate animals. These results indicate that social environment has an effect on the rewarding properties of morphine. It suggests that exposure to different peers can alter the abuse potential of opioids and potentially other illicit drugs.
社会/同伴影响是青少年吸毒的最强预测因素之一。然而，这个重要的主题在临床前研究中并没有得到太多关注。我们最近观察到，接触不同的社会伙伴会调节吗啡的运动敏化。对药物滥用的高运动反应的敏感性是对其他药物引起的行为敏感性的预测指标。因此，本研究探讨了接触不同的社会伙伴如何影响吗啡的奖赏特性。所有动物均在一个笼子中以每笼四只的方式分组饲养，饲养条件分为两种，分别称为“仅单独饲养”和“同笼饲养”。在混合处理条件下，吗啡和盐水处理的小鼠被一起饲养。这些组分别称为“吗啡同笼饲养”和“盐水同笼饲养”。在分开处理条件下，笼子里的所有老鼠都接受吗啡（即“仅吗啡”）或盐水（即“仅盐水”）治疗，并且笼子之间是视觉隔离的。所有动物在接受单次 10、20 或 40mg/kg 吗啡或盐水处理后，单独接受单次吗啡条件位置偏好（CPP）获得测试。正如预期的那样，单次处理在仅接受吗啡的动物中建立了吗啡 CPP，但在仅接受盐水的动物中没有建立。值得注意的是，吗啡同笼饲养的动物没有获得吗啡 CPP。此外，40mg/kg 吗啡足以在盐水同笼饲养的动物中建立吗啡 CPP。这些结果表明社会环境对吗啡的奖赏特性有影响。这表明接触不同的同伴可以改变阿片类药物和其他潜在非法药物的滥用潜力。
