KOP-r agonist U50,488H produces strong aversion and anxiety/depression-like behaviors that enhance alcohol intake and promote alcohol seeking and relapse-like drinking in rodents. Mammalian target of rapamycin complex 1 (mTORC1) pathway in mouse striatum is highly involved in excessive alcohol intake and seeking, and in the U50,488H-induced conditioned place aversion. Therefore, we hypothesized that KOP-r activation increases alcohol consumption through the mTORC1 activation. This study focuses on: (1) how chronic excessive alcohol drinking (4-day drinking-in-the-dark paradigm followed by 3-week chronic intermittent access drinking paradigm [two-bottle choice, 24-h access every other day]) affected nuclear transcript levels of the mTORC1 pathway genes in mouse nucleus accumbens shell (NAcs), using transcriptome-wide RNA sequencing analysis; and (2) whether selective mTORC1 inhibitor rapamycin could alter excessive alcohol drinking and prevent U50,488H-promoted alcohol intake. Thirteen nuclear transcripts of mTORC1 pathway genes showed significant up-regulation in the NAcs, with two genes down-regulated, after excessive alcohol drinking, suggesting the mTORC1 pathway was profoundly disrupted. Single administration of rapamycin decreased alcohol drinking in a dose-dependent manner. U50,488H increased alcohol drinking, and pretreatment with rapamycin, at a dose lower than effective doses, blocked the U50,488H-promoted alcohol intake in a dose-dependent manner, indicating a mTORC1-mediated mechanism. Our results provide supportive and direct evidence relevant to the transcriptional profiling of the critical mTORC1 genes in mouse NAc shell: with functional and pharmacological effects of rapamycin, altered nuclear transcripts in the mTORC1 signaling pathway after excessive alcohol drinking may contribute to increased alcohol intake triggered by KOP-r activation.

KOP-r 激动剂 U50,488H 会产生强烈的厌恶和焦虑/抑郁样行为，从而增加啮齿动物的酒精摄入量并促进酒精寻求和类似饮酒。小鼠纹状体中雷帕霉素复合物 1 (mTORC1) 通路的哺乳动物靶点高度参与过度饮酒和寻求，以及 U50,488H 诱导的条件性位置厌恶。因此，我们假设 KOP-r 激活通过 mTORC1 激活增加酒精消耗。这项研究的重点是：（1）如何长期过度饮酒（4 天在黑暗中饮酒范式，然后是 3 周慢性间歇性饮酒范式 [两瓶选择，每隔一天 24 小时饮酒]）使用全转录组 RNA 测序分析影响小鼠伏隔核 (NAcs) 中 mTORC1 通路基因的核转录水平；(2) 选择性 mTORC1 抑制剂雷帕霉素是否可以改变过度饮酒并防止 U50,488H 促进酒精摄入。mTORC1 通路基因的 13 个核转录本在 NAc 中显示出显着上调，其中两个基因在过量饮酒后下调，表明 mTORC1 通路被严重破坏。雷帕霉素的单次给药以剂量依赖性方式减少饮酒。U50,488H 增加饮酒量，并且用低于有效剂量的雷帕霉素预处理以剂量依赖性方式阻断 U50,488H 促进的酒精摄入，表明 mTORC1 介导的机制。我们的结果提供了与小鼠 NAc 壳中关键 mTORC1 基因的转录谱相关的支持性和直接证据：