Nicotine competition with light control of conditioned responding

描述（由申请人提供）：药物滥用的生理效应与药物使用环境中存在的其他刺激有关。这些关联在吸毒行为的获得、维持和复发中起着不可或缺的作用。在人类烟草使用者中，尼古丁是在各种其他刺激存在的情况下体验到的。这些其他刺激物通常是戒烟行为治疗的对象。因此，更好地了解尼古丁如何与其他刺激相互作用以控制条件反应可能有助于戒烟行为治疗策略。本研究的目的是系统地研究食欲巴甫洛夫辨别任务中离散的内感受性尼古丁神经递质和外感受性光神经递质之间的线索竞争。在具体目标1中，我们将确定尼古丁遮挡光是否依赖于尼古丁剂量。大鼠将使用一种复合刺激进行训练，其中同时静脉输注尼古丁和轻微的呈现，然后是短暂的蔗糖输送。在单独测试时，遮蔽将由每个元素对条件反应的相对控制来决定。我们还将研究外感受性光和内感受性尼古丁CSs之间的阻断现象。在特异性目标2中，大鼠将接受尼古丁或与蔗糖递送可靠配对的光的训练。在获得条件反应后，再加入另一个元素（即尼古丁注入或光线），形成复合条件刺激。再一次，大鼠将分别测试对每个元素的条件反应控制。我们预计，首先与蔗糖配对的刺激将阻断对随后增加的刺激的条件反应。这项研究的发现将填补我们对与尼古丁有关的联想学习过程的理解的重要空白，并可能有助于戒烟行为治疗策略。

DESCRIPTION (provided by applicant): The physiological effects of drugs of abuse form associations with other stimuli present in the environment in which the drug is experienced. These associations play an integral role in the acquisition, maintenance, and relapse of drug-taking behavior. In human tobacco users nicotine is experienced in the presence of a variety of other stimuli. These other stimuli are often the object of behavioral treatments for smoking cessation. Therefore, a better understanding how nicotine interacts with other stimuli for control of a conditioned response may assist smoking cessation behavioral treatment strategies. The goal of the present proposal is to systematically examine cue competition between a discrete interoceptive nicotine CS and an exteroceptive light CS in an appetitive Pavlovian discrimination task. In Specific Aim 1 we will determine whether nicotine overshadowing of the light is dependent on nicotine dose. Rats will be trained using a compound stimulus in which the concurrent intravenous infusion of nicotine and a light presentation will be reliably followed by a brief sucrose delivery. Overshadowing will be determined by the relative control of conditioned responding by each of the elements when they are tested separately. We will also examine the blocking phenomenon between the exteroceptive light and interoceptive nicotine CSs. In Specific Aim 2, rats will be trained with either nicotine or the light paired reliably with the sucrose delivery. After acquisition of the conditioned response, the other element (i.e., nicotine infusion or light) will be added to create the compound conditioned stimulus. Again, rats will then be tested for control of conditioned responding to each element separately. We expect that the stimulus that is first paired with sucrose will block conditioned responding to the subsequently added stimulus. The findings of the proposed research will fill an important gap in our understanding of associative learning processes involving nicotine and may assist smoking cessation behavioral treatment strategies.