Social Influences on Drug-Seeking Behavior

描述(由申请人提供)：流行病学研究一直报告说，青少年或年轻人是否会使用毒品的最可靠预测因素之一是他或她的朋友是否使用毒品。同龄人之间物质使用的高符合率的原因尚不完全清楚，但两种类型的理论受到了最多的关注。选择理论认为，个人自我选择进入的社会群体是 类似于他们自己，而社会化(或社会学习)理论认为，一个社会群体的成员使用物质使用行为，而其他群体成员模仿这些行为。考察社会影响对人类药物自我管理作用的实验研究是有限的，因为伦理约束限制了物质使用的模型化程度。在动物身上的实验研究是有限的，因为在测试期间，受试者通常被从他们的家环境中移走，并与他们的笼子分开。这代表了动物模型的显著局限性，因为人类的药物使用通常发生在他人在场的情况下，而这些其他人的行为(即他们是否也在使用药物)可能会影响个人的药物消费。拟议的项目描述了使用定制的操作调节室，允许在同一个室中同时在多个动物身上检查静脉注射药物的自我给药。在一系列实验中，我们将测试动物是否选择具有相似自我管理历史的其他老鼠(正如选择理论预测的那样)，以及大鼠是否模仿同龄人的自我管理行为(正如社会化理论预测的那样)。由于社会化理论进一步预测，针对社会环境的干预措施将影响药物自我管理，因此我们将研究拥有也自我管理可卡因的同伴(即，同伴使用者)与不自我管理可卡因的同伴(即，同伴不使用可卡因)的影响。我们的中心假设是，在与可卡因接触的同伴配对的大鼠中，可卡因自我给药会增加，而在与不能接触可卡因的同伴配对的大鼠中，可卡因的自我给药会减少。此外，鉴于NIDA高度重视在临床前和临床研究中调查性别差异，所有研究都将同时使用男性和女性受试者。

DESCRIPTION (provided by applicant): Epidemiological studies consistently report that one of the most reliable predictors of whether an adolescent or young adult will use drugs is whether or not his or her friends use drugs. The reasons for the high concordance rate of substance use among members of peer groups are not fully known, but two types of theories have received the most attention. Selection theories suggest that individuals self-select into social groups that are similar to themselves, whereas socialization (or social-learning) theories propose that members of a social group model substance use behaviors and other group members imitate those behaviors. Experimental studies examining the role of social influence on drug self-administration in humans are limited because ethical constraints limit the degree to which substance use can be modeled. Experimental studies in animals are limited because subjects are typically removed from their home environment and separated from their cagemates during testing. This represents a significant limitation of animal models, because drug use in humans typically occurs in the presence of others, and the behavior of these other people (i.e., whether or not they are also using drugs) may influence the drug consumption of the individual. The proposed project describes the use of custom-built operant-conditioning chambers that permit intravenous drug self- administration to be examined in multiple animals at the same time and in the same chamber. In a series of experiments, we will test whether animals choose other rats that share a similar self- administration history (as selection theories predict) and whether rats imitate the self-administration behavior of a peer (as socialization theories predict). Because socialization theories further predict that interventions targeting the social environment will influence drug self-administration, we will examine the impact of having a companion that also self-administers cocaine (i.e., a peer user) versus the impact of having a companion that does not self-administer cocaine (i.e., a peer nonuser). Our central hypothesis is that cocaine self-administration will be increased in rats paired with a companion with access to cocaine and decreased in rats paired with a companion without access to cocaine. Also, given the high scientific priority that NIDA places on investigating sex differences in preclinical and clinical research, all studies will employ both male and female subjects.