KATP Channels as Downstream targets of adenylyl cyclases during opioid tolerance and withdrawal

KATP 通道作为阿片类药物耐受和戒断期间腺苷酸环化酶的下游靶标

• 批准号: 10451672
• 负责人: Amanda Helen Klein
• 金额: $ 56.27万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-08-01 至 2026-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10451672
• 关键词: ATP sensitive potassium channel complex; Acute; Address; Adenoviruses; Adenylate Cyclase; Affect; Agonist; Analgesics; Attenuated; Basic Science; Cells; Chronic; Chronic inflammatory pain; Clinical; Coupled; Cyclic AMP; Cyclic AMP-Dependent Protein Kinases; Data; Development; Down-Regulation; Drug Targeting; Drug usage; Electrophysiology (science); Exposure to; Financial cost; Future; G-Protein-Coupled Receptors; GTP-Binding Proteins; Goals; Human; Hypersensitivity; Hypertrophy; In Situ Hybridization; In Vitro; Incidence; Intervention; Intrathecal Injections; Knowledge; Lead; Mechanics; Mediator of activation protein; Mission; Molecular; Morphine; Mus; National Institute of Drug Abuse; Nerve Fibers; Nervous system structure; Neural Conduction; Neuraxis; Neurons; Nociceptors; Opioid; Opioid agonist; Outcome; Patients; Peripheral; Pharmacology; Play; Potassium; Potassium Channel; Protein Isoforms; Public Health; Recording of previous events; Research; Rodent Model; Signal Transduction; Signal Transduction Pathway; Spinal Cord; Spinal Ganglia; Therapeutic; United States; Up-Regulation; Viral Vector; Withdrawal; Withdrawal Symptom; Work; adenylyl cyclase 1; antagonist; base; chronic pain relief; combat; drug development; genetic approach; genetic predictors; improved; in vitro Assay; in vitro activity; in vivo; innovation; knock-down; mu opioid receptors; neurobiological mechanism; neuronal excitability; neurophysiology; novel; novel therapeutics; opiate tolerance; opioid abuse; opioid exposure; opioid misuse; opioid use; opioid withdrawal; pain patient; pain processing; pain signal; prescription opioid; prevent; response; sciatic nerve; spontaneous pain

Project Summary The proposed research is relevant to public health because opioid use is prevalent in the United States and the human and financial costs associated with tolerance and withdrawal are at crisis levels. In order to reduce opioid abuse and misuse, our long-term goal is to determine the intracellular mechanisms to lead to these clinical problems. The objective of the proposed research is to understand the molecular involvement of adenylyl cyclase signaling and potassium channels in the peripheral and central nervous system during chronic opioid exposure using rodent models. A great deal of work has been done investigating the paradoxical phenomena of hypertrophied adenylyl cyclase activity and expression that occurs during chronic opioid exposure. The central hypothesis is that increased activity adenylyl cyclase and downstream mediators decrease KATP channel activity, leading to neuronal depolarization and increased hypersensitivity and spontaneous pain. The rationale of this proposal is that its completion will identify key intracellular targets of adenylyl cyclases, including potassium channels such as ATP-sensitive potassium (KATP) channels, which will help us to classify molecules that alter neuronal excitability and may play a key role in hypersensitivity during chronic opioid exposure. Given the history of research into adenylyl cyclase and inhibitory G-protein coupled signaling in the nervous system, it is surprising that fundamental questions still exist as to how these molecules affect neurophysiology of pain processing. Our first hypothesis is that overall expression of adenylyl cyclase 1 in the dorsal root ganglia and spinal cord increases after chronic morphine exposure. Our second hypothesis is that upregulation of adenylyl cyclase 1, and consequently cAMP, protein kinase A, and Epac molecules decrease KATP channel activity in vitro. Our third hypothesis is that upregulation of KATP channel subunits in the dorsal root ganglia and spinal cord using intrathecal injection of adenovirus viral vectors will improve mechanical hypersensitivity, mobility, and nerve conduction in mice after upregulated adenylyl cyclase during chronic opioid exposure. These approaches should prove to be complementary to one another and will provide the greatest opportunity to observe changes that occur in the nervous system after chronic opioid exposure. We plan on addressing these hypotheses through an innovative combination of in situ hybridization, electrophysiology, and potassium flux assays in vitro, and genetic approaches in vivo. The proposed work is important because completion of these studies will determine if the inverse relationship between adenylyl cyclase and KATP channel functionality could ultimately underlie and promote pain signaling seen clinically during opioid tolerance and withdrawal. KATP channels present an unutilized and interesting target for the development of drugs to treat opioid abuse and misuse. These results will have a positive impact because they will provide an increased knowledge and understanding of these signal transduction pathways during opioid exposure may assist in the mission to find better alternatives to current analgesic therapies for patients.

项目摘要 这项拟议的研究与公共卫生有关，因为阿片类药物的使用在美国和人类中很普遍， 与容忍和退出有关的财务成本处于危机水平。为了减少阿片类药物滥用和误用， 我们的长期目标是确定导致这些临床问题的细胞内机制。的目的 建议的研究是了解腺苷酸环化酶信号传导和钾通道的分子参与， 使用啮齿动物模型在慢性阿片样物质暴露期间的外周和中枢神经系统。大量的工作已经 研究肥大腺苷酸环化酶活性和表达的矛盾现象， 慢性阿片类药物暴露。中心假设是腺苷酸环化酶及其下游的活性增加， 介质降低KATP通道活性，导致神经元去极化和超敏反应增加， 自发性疼痛。这个建议的基本原理是，它的完成将确定腺苷酸的关键细胞内目标 环化酶，包括钾通道，如ATP敏感钾通道（KATP），这将有助于我们分类 改变神经元兴奋性的分子，并可能在慢性阿片类药物暴露期间的超敏反应中发挥关键作用。 考虑到神经系统中腺苷酸环化酶和抑制性G蛋白偶联信号的研究历史， 令人惊讶的是，关于这些分子如何影响疼痛处理的神经生理学的基本问题仍然存在。我们 第一个假设是腺苷酸环化酶1在背根神经节和脊髓中的总体表达在 慢性吗啡暴露我们的第二个假设是腺苷酸环化酶1的上调，从而cAMP， 蛋白激酶A和Epac分子在体外降低KATP通道活性。我们的第三个假设是， 鞘内注射腺病毒载体， 腺苷酸环化酶上调后改善小鼠机械超敏性、活动性和神经传导 慢性阿片类药物暴露这些方法应证明是相辅相成的，并将提供最大的 有机会观察慢性阿片类药物暴露后神经系统发生的变化。我们计划解决 通过原位杂交、电生理学和钾通量测定的创新组合， 体外和体内遗传方法。拟议的工作是重要的，因为完成这些研究将 确定腺苷酸环化酶和KATP通道功能之间的反比关系是否最终成为 并促进阿片耐受和戒断期间临床上可见的疼痛信号。KATP通道呈现未利用的 并且是治疗阿片类药物滥用和误用的药物开发的有趣目标。这些结果将产生积极的 影响，因为它们将提供更多的知识和理解这些信号转导途径， 阿片类药物暴露可能有助于使命，以找到更好的替代目前的镇痛治疗的患者。