Drug addiction is a chronic mental disorder characterized by frequent relapses. Contextual cues associated with drug use to play a critical causal role in drug-seeking behavior. The hippocampus has been implicated in encoding drug associative memories. Here we examine whether the dorsal hippocampus mediates context-induced reinstatement of alcohol-seeking. Male Long-Evans rats were trained to self-administer alcohol in Context A. Alcohol self-administration was extinguished in a distinct context (Context B). On the test day, animals were re-exposed to the alcohol Context A or the extinction Context B. Next, to assess a causal role for the dorsal hippocampus in context-induced alcohol-seeking, on the test day, we injected cobalt chloride (CoCl2; a nonselective synapse inhibitor) or vehicle into the dorsal hippocampus, and 15 min later, rats were tested by re-exposing them to the drug-associated context. The re-exposure to the alcohol-associated Context A reinstated alcohol seeking and increased Fos-positive cells in the dorsal hippocampus neurons (CA1, CA3, and Dentate Gyrus). Pharmacological inactivation with cobalt chloride of the dorsal hippocampus attenuated the reinstatement of alcohol-seeking. Our data suggest that the dorsal hippocampus may be involved in context-induced alcohol-seeking behavior.

毒瘾是一种以频繁复发为特征的慢性精神障碍。与吸毒相关的背景线索在寻求毒品的行为中起着关键的因果作用。海马体与编码药物联想记忆有关。在这里，我们检查背侧海马体是否介导上下文诱导的酒精寻求恢复。雄性 Long-Evans 大鼠被训练在情境 A 中自我管理酒精。酒精自我管理在不同情境（情境 B）中消失。在测试当天，动物再次暴露于酒精环境 A 或灭绝环境 B。接下来，为了评估背侧海马在环境诱导的酒精寻求中的因果作用，在测试当天，我们注射了氯化钴（ CoCl2；一种非选择性突触抑制剂）或载体进入背海马体，15 分钟后，通过将大鼠重新暴露于与药物相关的环境中来测试大鼠。重新暴露于与酒精相关的上下文 A 恢复了酒精寻求并增加了背海马神经元（CA1、CA3 和齿状回）中的 Fos 阳性细胞。用氯化钴对背侧海马进行药理学灭活减弱了寻求酒精的恢复。我们的数据表明，背侧海马体可能与环境诱导的寻酒行为有关。