Understanding multisensory hypersensitivity in chronic pain states

了解慢性疼痛状态下的多感觉超敏反应

• 批准号: 9332614
• 负责人: Mary Magdalen Heinricher
• 金额: $ 37.48万
• 依托单位: OREGON HEALTH & SCIENCE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-01-15 至 2020-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9332614
• 关键词: Animal Model; Animals; Behavior; Behavioral; Brain; Brain Stem; Cells; Chronic; Clinical; Dependence; Electrophysiology (science); Elements; Endocrine; Equilibrium; Esthesia; Functional disorder; Hyperalgesia; Hypersensitivity; Hypothalamic structure; Inflammation; Inflammatory; Laboratories; Light; Mechanics; Migraine; Modality; Modeling; Neurons; Nociception; Output; Pain; Pain Disorder; Painless; Pathway interactions; Patients; Persistent pain; Phonophobias; Photophobia; Photosensitivity; Play; Rattus; Reporting; Response to stimulus physiology; Rodent Model; Role; Sensory; Smell Perception; Stimulus; Stress; Structure; System; Testing; Thalamic structure; Trigeminal System; Visual Pathways; Work; active control; base; behavioral response; chronic pain; extracellular; insight; multisensory; neurobiological mechanism; relating to nervous system; response; sound; transmission process; visual stimulus

PROJECT SUMMARY Many chronic pain patients complain of abnormal sensitivity to multiple sensory modalities, including light, sound, and smell. The underlying neural basis remains a puzzle and these claims are often viewed with suspicion, since sensory acuity per se is not enhanced, nor is there amplified processing in primary sensory pathways. The central thesis of this proposal is that dysfunction of brainstem pain-modulating systems, already thought to contribute to pain in these conditions, is also likely to play a role in multisensory hypersensitivity. This hypothesis is based on our unexpected observation that a subset of pain-modulating neurons in the rostral ventromedial medulla, the final output of an important brainstem pain-modulating system, respond to light. In three Specific Aims using single-cell recording approaches in rat, we will fully characterize the RVM response to light, generating stimulus-response functions and establishing the relevant spectrum. We will also determine whether photoresponsiveness of these neurons is enhanced in an animal model of migraine headache (where photosensitivity is well documented) or in a persistent inflammatory state. Finally, we will investigate “top-down” modulation of photoresponsiveness from a higher brain structure known to contribute to stress-induced hyperalgesia and implicated in endocrine, autonomic, and behavioral responses to mild stress. The present proposal brings together electrophysiological and behavioral approaches to determine how light engages pain-modulating systems, effectively converting a visual stimulus to a somatic sensation, producing discomfort and aversion. These studies will provide fundamental insights into the neurobiological mechanisms of multisensory hypersensitivity, information critical to developing more appropriate treatments for migraine and other chronic pain disorders.

项目总结