Philpot R M, Kirstein C L
Department of Psychology and Pharmacology, University of South Florida, Tampa 33620, USA.
Neuroreport. 1998 May 11;9(7):1359-63. doi: 10.1097/00001756-199805110-00020.
Substance abuse is a major issue in today's society and is an issue of critical importance in the adolescent population. Research indicates that substance use is often initiated during the adolescent period and that brain reward areas are still undergoing changes during this time. Despite this, little research has investigated the effects of repeated drug use on the reward mechanisms of periadolescent animals. For this reason, the present study examined the effects of repeated ethanol (EtOH) administration on the responsiveness of the nucleus accumbens septi (NAcc) to either EtOH or saline challenge. The data indicate that repeated exposure to EtOH produces temporal shifts in the dopaminergic (DAergic) activity of the NAcc, with peak activity occurring earlier. Importantly, following repeated injections of EtOH, saline injections alone elicit DA increases in the NAcc suggesting that the context of alcohol administration produces fundamental changes in the way that neurochemical reinforcement mechanisms respond. The expectancy of the drug alone elicits reward-related activity within the NAcc.
药物滥用是当今社会的一个主要问题，在青少年群体中也是一个至关重要的问题。研究表明，药物使用往往始于青少年时期，且在此期间大脑奖赏区域仍在发生变化。尽管如此，很少有研究调查反复使用药物对青春期前后动物奖赏机制的影响。因此，本研究考察了反复给予乙醇（EtOH）对伏隔核（NAcc）对EtOH或生理盐水激发的反应性的影响。数据表明，反复接触EtOH会使NAcc的多巴胺能（DAergic）活动出现时间上的变化，峰值活动出现得更早。重要的是，在反复注射EtOH后，单独注射生理盐水会引起NAcc中多巴胺增加，这表明酒精给药的环境会使神经化学强化机制的反应方式发生根本变化。仅药物的预期就会引发NAcc内与奖赏相关的活动。
