Cannabidiol and terpenoid interactions in amygdalar regulation of pain states

项目摘要 慢性疼痛影响多达三分之一的美国人口，并且依赖阿片类药物来治疗慢性疼痛。 疼痛在很大程度上促成了阿片类药物的流行。开发替代性疼痛疗法对于 减少阿片类药物的使用，植物大麻素大麻二酚（CBD）是一个有前途的候选者。我们有 表明CBD有能力在3周内减少小鼠的慢性神经性疼痛样反应。 萜类化合物（如β-carbellene），也发现在大麻植物，是一个潜在的第二类 大麻中的活性化合物可能具有镇痛作用，尽管它们 对体外和体内的药效学性质知之甚少。同样，也有一个不完整的 了解CBD和萜类化合物如何通过自身或组合（“环境”）产生抗伤害感受， 并且它们的“疼痛控制”的脊髓上神经药理学机制仍然未知。拟议 实验将首先测试CBD和萜类化合物的特定组合是否能产生短期的 炎性和长期神经性抗伤害感受而无耐受性。然后我们将建立 CBD和萜类化合物在疼痛的关键脑核，基底外侧杏仁核中的作用。最后我们将 确定CBD和萜类化合物在体外和体内的药理学和生物化学信号传导谱， vivo.在目标1中，我们将使用CBD和萜类化合物的混合物，研究者给药以及我们的明胶 自我给药模型，并测量部分坐骨神经结扎后的消耗和疼痛评分， 确定CBD和/或萜类化合物是否在长期疼痛中提供镇痛益处。我们还将核实 这些混合物本身并不具有奖励性，而这对药物滥用责任至关重要。在目标2中，我们 测试杏仁核是否是CBD/萜类镇痛作用的关键脑回路部位，使用单细胞 疼痛状态下杏仁核神经元的钙成像，同时局部注射CBD和萜类化合物 进入杏仁核产生镇痛作用此外，我们将敲除大麻素受体和其他假定的 BLA内CBD/萜类化合物作用的位点，以确定每种作用在产生行为和 生理反应。在目标3中，我们将使用体外和体内系统来确定重要的生化指标， CBD和萜类化合物在其假定的受体靶点上的作用特征。我们将测量细胞信号活动 通过动态质量再分布（DMR）、MAP激酶信号传导和活性氧物质的产生。 这些目标将告知公众健康长期使用大麻二酚/萜类化合物的益处和风险， 以及提供关键的机制洞察力，这将有助于开发和了解是否定制药物 大麻治疗慢性疼痛的方法可用于治疗。

PROJECT SUMMARY Chronic pain affects up to one third of the United States population, and the reliance on opioids to treat chronic pain has contributed substantially to the opioid epidemic. Developing alternative pain therapies is critical to reducing the use of opioids, and the phyto-cannabinoid cannabidiol (CBD) is a promising candidate. We have shown that CBD has the ability to reduce chronic neuropathic pain-like responses in mice over 3 weeks. Terpenoids (eg beta-caryophyllene), also found in the cannabis plant, are a potential second class of pharmacologically active compounds in cannabis with possible analgesic benefits, although their pharmacodynamic properties in vitro and in vivo are poorly understood. Likewise, there is an incomplete understanding of how CBD and terpenoids produce anti-nociception, by themselves or combined (“entourage”), and their supraspinal neuropharmacological mechanisms of “pain control” remain unknown. The proposed experiments will first test whether specific combinations of CBD and terpenoids can produce short-term inflammatory and long-term neuropathic antinociception without tolerance. We will then establish the action of CBD and terpenoids in a critical brain nucleus for pain, the basolateral amygdala. Finally, we will determine the pharmacological and biochemical signaling profiles of CBD and terpenoids in vitro and in vivo. In Aim 1, we will use mixtures of CBD and terpenoids, investigator administered as well as in our gelatin self-administration model, and measure both consumption and pain scores after partial sciatic nerve ligation to determine if CBD and/or terpenoids provide analgesic benefit over protracted periods of pain. We will also verify that these mixtures are not inherently rewarding, which is critical for substance abuse liability. In Aim 2, we will test whether the amygdala is a critical brain circuit site for CBD/terpenoid analgesic action using single cell calcium imaging of amygdalar neurons during pain states, in parallel with local injections of CBD and terpenoids into the amygdala to produce analgesia. Further, we will knock out cannabinoid receptors and other putative sites of CBD/terpenoid action within the BLA to establish necessity of each in producing behavioral and physiological responses. In Aim 3, we will use in vitro and in vivo systems to determine the important biochemical features of CBD and terpenoid action at their putative receptor targets. We will measure cellular signaling activity via dynamic mass redistribution (DMR), MAP Kinase signaling, and the generation of reactive oxygen species. These aims will inform public health about the benefits and risks of long-term cannabidiol/terpenoid usage, as well as providing crucial mechanistic insight that will help develop and understand whether tailored medicinal cannabis approaches for chronic pain can be harnessed for therapeutic benefit.