Ethanol & Anxiety: Cellular Mechanisms

酒精滥用会导致行为和神经生物学功能的显著变化。在这些行为中 持续虐待的关键表现是类焦虑和寻求奖励的显著增加 行为。这些结果是密切相关的，共同推动了随后的乙醇滥用。这个 杏仁外侧核/基底外侧核在焦虑和奖赏寻求的调节中起着关键作用。近期 对药物幼稚动物的条件性行为的研究表明，隔离但混合的种群 杏仁核基底外侧主神经元独立参与与“奖赏”和“厌恶”相关的神经元 电路。重要的是，这种隔离也反映在突触水平上，奖赏或厌恶影响着 谷氨酸能突触以一种电路特异性和相互排斥的方式连接到这些群体上。然而，在 尽管在幼稚的情况下，这种功能上的隔离，追求奖励和“厌恶”通常是共同的 在有药物经验的动物身上表达。而且，我们已经证明了依赖类酒精暴露的强势 以一种似乎非隔离的方式改变BLA突触功能。奖赏的并列-/ BLA内的情感回路控制，以及慢性乙醇对参与这些控制的神经元的影响 电路，表明可能的细胞机制驱动巧合的奖赏寻求和负面影响 在酒精依赖之后。这导致了当前应用程序的中心假设 不同BLA输入下的协作突触可塑性控制奖赏寻求和奖赏寻求之间的交互作用 长期接触酒精后出现的负面情绪状态。为了验证这一假设，我们提出了三个具体的假设 目标。目标1将测试工作假设，即慢性酒精，不同于自然条件行为， 促进主神经元的BLA突触功能，独立于其投射靶点。我们将整合 用逆行示踪法和电生理学方法测量突触功能和固有功能 参与不同的“奖赏”和“厌恶”回路的差异“价态”BLA神经元的特性。 目标2将验证慢性乙醇促进突触前易化是必要的工作假设 足以在不同的突触上发展突触后可塑性。我们认为这是由乙醇引起的 将光遗传学、化学遗传学和体外电生理学融为一体的异质突触合作 分析确定的输入(前额叶和无颗粒岛叶皮质)之间的功能耦合，并2)破坏它们的 功能交互。最后，对于目标3，我们将测试乙醇失调的工作假设 BLA-PRL突触通过整合调控慢性酒精中毒后的负性情绪和奖赏寻求 与酒精依赖、饮酒和焦虑行为相关的化学遗传学。建议的工作是 技术创新和意义重大，因为它利用最先进的基于电路的方法来 直接定义了调节酒精依赖的负面情绪和奖励的神经生物学机制- 寻找酒精滥用和上瘾的特征。

Ethanol abuse produces marked changes in behavior and neurobiological function. Among the behavioral manifestations critical for continued abuse are the profound increases in anxiety-like and reward-seeking behaviors. These outcomes are intimately related and together drive subsequent ethanol abuse. The lateral/basolateral amygdala plays a critical role in the regulation of both anxiety and reward-seeking. Recent work with conditioned behaviors in drug naïve animals suggests that segregated but intermingled populations basolateral amygdala principal neurons independently participate within `reward'- and `aversion'-related circuits. Importantly, this segregation is also reflected at the synaptic level with reward or aversion influencing glutamatergic synapses onto these populations in a circuit-specific and mutually exclusive manner. Yet, in spite of this functional segregation in the naïve condition, reward-seeking and `aversion' are typically are co- expressed in drug-experienced animals. And, we have shown that dependence-like ethanol exposure robustly alters BLA synaptic function in what appears to be a non-segregated fashion. The juxtaposition of reward-/ affective-circuit control within the BLA, and the effects of chronic ethanol across neurons participating in these circuits, suggests possible cellular mechanisms driving coincidental reward-seeking and negative affect following alcohol dependence. This leads to the CENTRAL HYPOTHESIS of the current application that cooperative synaptic plasticity at distinct BLA inputs controls the interaction between reward-seeking and negative affective states that follow chronic ethanol exposure. To test this hypothesis, we propose three specific aims. Aim 1 will test the working hypothesis that chronic ethanol, unlike naturally conditioned behaviors, facilitates BLA synaptic function at principal neurons independent of their projection target. We will integrate retrograde tracing and electrophysiological approaches to measure both synaptic function and intrinsic properties of differentially `valenced' BLA neurons participating within distinct `reward' and `aversion' circuits. Aim 2 will test the working hypothesis that presynaptic facilitation by chronic ethanol is necessary and sufficient for the development of postsynaptic plasticity at distinct synapses. We this `ethanol-induced heterosynaptic cooperation' by integrating optogenetics, chemogentics, and in vitro electrophysiology to 1) assay functional coupling between defined inputs (prelimbic and agranular insular cortex) and 2) disrupt their functional interaction. Finally, for Aim 3, we will test the working hypothesis that ethanol dysregulation of BLA-PrL synapses governs both negative affect and reward seeking following chronic ethanol by integrating chemogenetics with dependence-related ethanol drinking and anxiety-like behavior. The proposed work is both technically innovative and significant because it utilizes state-of-the-art circuit-based approaches to directly define neurobiological mechanisms regulating both ethanol-dependent negative affect and reward- seeking which characterize alcohol abuse and addiction.