The University of Chicago, Department of Psychiatry and Behavioral Neuroscience, 5841 S. Maryland Avenue MC-3077, Chicago, IL 60637, United States.
Drug Alcohol Depend. 2010 Jun 1;109(1-3):175-80. doi: 10.1016/j.drugalcdep.2009.12.029. Epub 2010 Feb 21.
Stress is thought to contribute to both initiation and relapse to drug abuse. However, the mechanisms by which stress influences drug use are unclear. Interestingly, responses to acute administration of stimulant drugs resemble certain neuronal and hormonal responses to acute stress, and there is accumulating evidence that individual variation in the positive reinforcing or euphorigenic effects of a drug is related to individual differences in responsivity to acute stress.
In this study we evaluated relationships between physiological and subjective responses to a stressful task and to an oral dose of d-amphetamine in healthy adult volunteers (N=34). Individuals participated in four experimental sessions; two behavioral sessions involving a stressful task (i.e., public speech) or a non-stressful control task, and two drug sessions involving oral administration of d-amphetamine (20mg) or a placebo. The dependent measures included salivary cortisol, heart rate, mean arterial pressure, and subjective ratings of mood.
As expected, both stress and d-amphetamine increased cortisol, heart rate and blood pressure. Stress increased negative mood, whereas d-amphetamine induced prototypic stimulant effects and increased ratings of drug liking. Analyses revealed that increased negative mood states after stress were correlated with positive mood after amphetamine. In addition, increased cortisol after stress was correlated with positive mood responses to amphetamine. Finally, there were modest positive correlations between cortisol and heart rate increases after stress and mean arterial pressure after amphetamine.
These results support and extend previous observations that responses to acute stress are correlated with certain subjective, hormonal and cardiovascular effects of a stimulant drug.
压力被认为会导致药物滥用的开始和复发。然而，压力影响药物使用的机制尚不清楚。有趣的是，急性给予兴奋剂药物的反应类似于急性应激的某些神经元和激素反应，并且有越来越多的证据表明，药物的正强化或欣快效应的个体差异与个体对急性应激的反应性差异有关。
在这项研究中，我们评估了健康成年志愿者（N=34）对一项应激任务和口服 d-苯丙胺的生理和主观反应之间的关系。个体参加了四个实验阶段；两个行为阶段涉及一项应激任务（即公开演讲）或一项非应激对照任务，以及两个药物阶段涉及口服给予 d-苯丙胺（20mg）或安慰剂。依赖措施包括唾液皮质醇、心率、平均动脉压和情绪的主观评分。
正如预期的那样，应激和 d-苯丙胺都增加了皮质醇、心率和血压。应激增加了负性情绪，而 d-苯丙胺诱导了典型的兴奋剂效应，并增加了对药物的喜爱评分。分析表明，应激后负性情绪状态的增加与苯丙胺后的正性情绪相关。此外，应激后皮质醇的增加与苯丙胺后对正性情绪的反应相关。最后，应激后皮质醇和心率的增加与苯丙胺后平均动脉压之间存在适度的正相关。
这些结果支持并扩展了先前的观察结果，即急性应激反应与兴奋剂药物的某些主观、激素和心血管效应相关。
