Pathway-specific Intervention in Prelimbic Cortical Circuitry Decreases Cocaine-seeking

具体目标 对于患有物质使用障碍(Suds)的人来说，一个主要的挑战是缺乏有效的药物。 减少复发风险的治疗方法。环境中的药物预测线索是引发 复发和了解这些持久联系是如何形成和维持的，这是 临床前SUD研究。在这项提案中，我们建立在我们的发现的基础上，在结束后不久 可卡因自身给药(SA)，将脑源性神经营养因子(BDNF)注入前庭(PL) 前额叶皮质阻止可卡因SA诱导的关键谷氨酸相关可塑性的去磷酸化- 相关蛋白(PRPS)，包括GluN2A、GluN2B、ERK MAP激酶和CREB32，96。这一早期干预 使用BDNF还可以防止可卡因导致的PL-NA核心谷氨酸能传递的长期缺陷 促进后续的可卡因寻找9。相比之下，在禁欲的第一周结束时，蛋白激酶A (PKA)依赖的GluA1和CREB的磷酸化增强出现。当时，PL内部的BDNF 对复发没有影响，但PL内注入PKA抑制剂RP-cAMP可逆转 过度磷酸化，减少复发70，92。最近，我们已经展示了两相变化 戒酒第一周内的GluA1和pCREB与类似的头部双相变化有关 PL-NA核心神经元树突棘的直径(Dh)。这些数据刺激了总体假设 减少寻求毒品的干预措施必须根据神经适应的动态变化而量身定做 在上瘾周期的不同阶段出现。 在化学遗传学研究中，研究起源于PL皮质的特定通路对药物的贡献 寻找，我们发现PL-NA核心和PL-丘脑室旁后核(PPVT)通路 在早期戒断期间互相抵触对方的影响。PL-NA选择性依赖于cre的DREADD抑制 可卡因SA后立即被逆行转运的cre-AAV感染的核心神经元不受 但可逆转体内BDNF对后续药物寻找的抑制作用31。相比之下， 选择性抑制可卡因SA后立即的PL-pPVT通路可减少随后的可卡因- 寻求，一种被PL内部的BDNF31阻止的效果。有趣的是，我们还发现选择性抑制 PL-pPVT通路减少可卡因戒断大鼠的焦虑相关行为 PPVT减少了对可卡因的条件性厌恶，这表明可卡因参与了焦虑-和 帮助药物寻找的厌恶相关电路包括pPVT。 综上所述，我们的新发现提出了一种新的假设，即可卡因SA产生差异 对PL-NA核心和PL-pPVT通路的调节，以及这两个不同的电路共同支持未来 寻找毒品。在这项提案中，我们将使用特定路径的组合化学遗传学方法，切片 PL-NA核和PL-pPVT电路的电生理学和最新树突棘和PRP成像 探索在这个网络中发生的影响可卡因寻求和厌恶的依赖时间的可塑性。 我们将在下列目标中使用这些方法，这将在雄性和雌性大鼠身上进行。 目的1.脑源性神经营养因子对PL-NA核与PL-pPVT内PRPS及结构和突触可塑性的调节 早期戒断时的神经元。使用病毒载体的方法，我们将研究内PL的影响 脑源性神经营养因子注射对(A)树突棘可塑性和PRP的改变以及(B)PL-NA核的突触可塑性。 戒断早期的PL-PVT神经元。 目的2.与pPVT相比，PKA对PL-NA核心区PRPS及结构和突触可塑性的调节 戒断7天和30天后的神经元。(A)我们会研究抑制cAMP/PKA的效果 (A)树突棘可塑性和PRP的变化以及(B)PL-NA核的突触可塑性与PL- 戒断7天或30天后，PVT神经元有或没有复发测试。 目的3.PL-NA核心和PL-pPVT神经元在可卡因诱发的焦虑和厌恶中的作用 与戒毒后寻求可卡因的关系。我们将使用Rettro-GI DREADD方法来测试 抑制PL-NA核或PL-pPVT神经元(A)对戒断后即刻焦虑的影响 结束可卡因SA和(B)在可操作跑道任务之前或之后有条件地避免可卡因 可卡因SA随后进行线索诱导的复发测试。 科学影响：这些研究将扩大我们对如何逆转关键的神经适应的理解 在成瘾周期的不同阶段，潜在的前额叶功能障碍会引发药物复发- 寻找。通过了解时间动态的、不同的神经适应在PL网络调节中的作用 奖励和厌恶，我们可能能够发现新的治疗靶点，以减少药物寻求。

Specific Aims A major challenge for individuals suffering from substance use disorders (SUDs) is the lack of effective treatments that reduce relapse vulnerability. Drug predictive cues in the environment are powerful triggers for relapse and understanding how these persistent associations are formed and maintained is a critical focus of preclinical SUD research. In this proposal, we have built on our discovery that immediately after the end of cocaine self administration (SA), an infusion of brain-derived neurotrophic factor (BDNF) into the prelimbic (PL) prefrontal cortex prevents the cocaine SA-induced dephosphorylation of key glutamatergic-related plasticity- related proteins (PRPs), including GluN2A, GluN2B, ERK MAP kinase, and CREB32,96. This early intervention with BDNF also prevents prolonged cocaine-induced deficits in PL-NA core glutamatergic transmission that promote subsequent cocaine seeking9. In contrast, by the end of the first week of abstinence, protein kinase A (PKA)-dependent augmentation of GluA1 and CREB phosphorylation emerges. At that time, intra-PL BDNF has no effect on relapse8 but intra-PL infusion of a PKA inhibitor, Rp-cAMPs, reverses the hyperphosphorylation and decreases relapse70,92. More recently, we have shown that the biphasic changes in GluA1 and pCREB within the first week of abstinence are associated with similar biphasic changes in the head diameters (dH) of dendritic spines of PL–NA core neurons89. These data have spurred the overall hypothesis that interventions to decrease drug seeking must be tailored to the dynamic changes in neuroadaptations that emerge during different phases of the addiction cycle. In chemogenetic studies to investigate the contribution of specific pathways originating in PL cortex to drug seeking, we discovered that PL-NA core and PL-posterior paraventricular thalamic nucleus (pPVT) pathways oppose each others’ effects during early withdrawal. Selective cre-dependent DREADD inhibition of PL-NA core neurons infected with a retrogradely transported cre-AAV immediately after cocaine SA has no effect by itself, but reverses the suppressive effect of intra-PL BDNF on subsequent drug seeking31. In contrast, selective inhibition of the PL-pPVT pathway immediately after cocaine SA decreases subsequent cocaine- seeking, an effect that is prevented by intra-PL BDNF31. Interestingly, we also found that selective inhibition of the PL-pPVT pathway reduces anxiety-related behavior in rats withdrawing from cocaine and inactivation of pPVT decreases conditioned aversion to cocaine, suggesting that cocaine’s engagement of anxiety- and aversion-related circuitry that contributes to drug seeking includes pPVT. Taken together, our new findings suggest the novel hypothesis that cocaine SA produces differential regulation of PL-NA core and PL-pPVT pathways and that these two distinct circuits conspire to support future drug seeking. In this proposal, we will use pathway-specific, combinatorial chemogenetic approaches, slice electrophysiology, and state-of-the-art dendritic spine and PRP imaging in PL-NA core and PL-pPVT circuitry to explore the time-dependent plasticity occurring in this network that influences cocaine seeking and aversion. We will use these approaches in the following aims that will be performed in male and female rats. Aim 1. BDNF regulation of PRPs and structural and synaptic plasticity in PL-NA core vs. PL-pPVT neurons during early withdrawal. Using viral vector approaches, we will investigate the effects of intra-PL BDNF infusion on (A) dendritic spine plasticity and PRP changes and (B) synaptic plasticity in PL-NA core vs. PL-PVT neurons during early withdrawal. Aim 2. PKA regulation of PRPs and structural and synaptic plasticity in PL-NA core vs. PL-pPVT neurons after 7 and 30 days of abstinence. (A) We will investigate the effects of inhibiting cAMP/PKA signaling on (A) dendritic spine plasticity and PRP changes and (B) synaptic plasticity in PL-NA core vs. PL- PVT neurons after 7 or 30 days of abstinence with or without relapse testing. Aim 3. The role of PL-NA core and PL-pPVT neurons in cocaine-induced anxiety and aversion in relationship to cocaine seeking after abstinence. We will use a retro-Gi DREADD approach to test the effects of inhibiting PL-NA core or PL-pPVT neurons (A) on withdrawal-induced anxiety immediately after the end of cocaine SA and (B) on conditioned avoidance of cocaine in an operant runway task before or after cocaine SA followed by cue-induced relapse testing. Scientific Impact: These studies will expand our understanding of how to reverse critical neuroadaptations underlying prefrontal dysfunctions during different phases of the addiction cycle that trigger relapse to drug- seeking. By understanding temporally dynamic, differential neuroadaptations in the PL networks regulating reward and aversion, we may be able to discover novel therapeutic targets to decrease drug-seeking.