Arvanitogiannis A, Sullivan J, Amir S
Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, 1455 de Maisonneuve Boulevard, West Montréal, Québec, Canada H3G 1M8.
Neuroscience. 2000;101(1):1-3. doi: 10.1016/s0306-4522(00)00401-2.
Repeated exposure to the psychostimulant drug, amphetamine, results in a persistent increase in the ability of the drug to elicit behavioral activation.(14,19) The development of sensitized responses to amphetamine involves long-lasting neuroadaptations within defined circuitry.(3,6,12,15,23) The behavioral expression of sensitization, however, can come under the control of specific environmental cues. Thus, the sensitized locomotor response to a challenge injection of amphetamine is greater if the drug is given in the environment previously associated with intermittent injections than if given in a different environmental context.(2,13,16,18,20,21) Contrary to the wealth of information on the significance of contextual cues, little is known about the importance of time cues in the expression of sensitized responding to amphetamine. In the present study we, therefore, asked whether time of injection might influence the expression of amphetamine sensitization. We found that time can readily act as a conditioned stimulus to control the expression of behavioral sensitization to amphetamine in rats. This finding is important for understanding the mechanisms underlying sensitization to psychostimulant drugs and its impact on behavior.
反复接触精神刺激药物苯丙胺会导致该药物引发行为激活的能力持续增强。（14,19）对苯丙胺致敏反应的发展涉及特定神经回路内的持久神经适应性变化。（3,6,12,15,23）然而，致敏反应的行为表现可能受特定环境线索的控制。因此，如果在先前与间歇性注射相关的环境中给予苯丙胺，那么对其激发注射的致敏运动反应会比在不同环境中给予时更大。（2,13,16,18,20,21）与关于情境线索重要性的大量信息相反，对于时间线索在苯丙胺致敏反应表达中的重要性知之甚少。因此，在本研究中，我们探讨了注射时间是否可能影响苯丙胺致敏反应的表达。我们发现时间很容易作为一种条件刺激来控制大鼠对苯丙胺行为致敏反应的表达。这一发现对于理解对精神刺激药物致敏的潜在机制及其对行为的影响具有重要意义。
