Segal Diana, Valyear Milan D, Chaudhri Nadia
Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montreal, Quebec, Canada.
Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montreal, Quebec, Canada.
Alcohol. 2022 Mar;99:70-81. doi: 10.1016/j.alcohol.2021.10.004. Epub 2021 Nov 3.
In male rats, physical contexts that are associated with alcohol can amplify the response to a discrete, alcohol-predictive conditioned stimulus (CS), and amplify prime-induced reinstatement. Here, we examined these effects as a function of biological sex. Male and female Long-Evans rats were acclimated to drinking ethanol (15% v/v) in their home cages. Next, they were trained to associate an auditory conditioned stimulus (CS) (10 s; white noise or clicker; 15 trials per session) with ethanol delivery (0.2 mL per CS; 3.0 mL per session) into a fluid port for oral intake. Training occurred in a distinctive context containing specific visual, olfactory, and tactile stimuli. During alternating sessions, rats were exposed to a second context wherein they did not receive ethanol. At test, CS trials occurred in both contexts without ethanol delivery. Rats then underwent extinction using repeated unreinforced presentations of the CS in both contexts. An alcohol-primed reinstatement test was then conducted, in which 0.2 mL of ethanol was presented at the start of the session and during the first CS trial, after which no ethanol was delivered for the remainder of the session. At both test and reinstatement, male rats made significantly more CS port-entries in the context associated with alcohol delivery than in the context in which alcohol was never experienced. Unlike males, female rats made a similar number of CS port-entries at the test in both the alcohol context and the neutral context. The reinstatement observed in female rats was also not affected by context. These findings suggest that the capacity of an alcohol-associated context to modulate responding to a discrete, alcohol-predictive cue is less pronounced in female than male rats.
在雄性大鼠中，与酒精相关的物理环境可增强对离散的、酒精预测性条件刺激（CS）的反应，并增强启动诱导的复吸。在此，我们研究了这些效应与生物性别的关系。将雄性和雌性长 Evans 大鼠在其饲养笼中适应饮用乙醇（15% v/v）。接下来，训练它们将听觉条件刺激（CS）（10 秒；白噪声或咔哒声；每次训练 15 次）与通过液体端口向口腔摄入的乙醇给药（每次 CS 给药 0.2 mL；每次训练 3.0 mL）相关联。训练在包含特定视觉、嗅觉和触觉刺激的独特环境中进行。在交替训练期间，大鼠暴露于第二个环境中，在此环境中它们不接受乙醇。在测试时，CS 试验在两个环境中进行，均不给药乙醇。然后在两个环境中使用 CS 的重复无强化呈现对大鼠进行消退训练。接着进行酒精启动的复吸测试，在训练开始时和第一次 CS 试验期间给予 0.2 mL 乙醇，此后在训练的剩余时间内不再给药乙醇。在测试和复吸时，雄性大鼠在与酒精给药相关的环境中比在从未接触过酒精的环境中做出的 CS 端口进入次数显著更多。与雄性不同，雌性大鼠在酒精环境和中性环境中的测试中做出的 CS 端口进入次数相似。在雌性大鼠中观察到的复吸也不受环境的影响。这些发现表明，与酒精相关的环境调节对离散的、酒精预测性线索反应的能力在雌性大鼠中比在雄性大鼠中不那么明显。
