ESOPHAGO-LARYNGEAL ADDUCTOR REFLEX

食管-喉内收肌反射

• 批准号: 2518037
• 负责人: Nancy Marie Bauman
• 金额: $ 11.29万
• 依托单位: UNIVERSITY OF IOWA
• 依托单位国家: 美国
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-09-01 至 2001-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2518037
• 关键词: afferent nerve; apnea; central nervous system stimulants; dogs; efferent nerve; electromyography; embryo /fetus; esophagus; hypertension; larynx; neurons; neurotransmitter receptor; neurotransmitters; reflex; reflux esophagitis; respiratory airway pressure; spasm; statistics /biometry; stereotaxic techniques; stimulus /response; substance P; tachycardia; vagus nerve

Stimulation of distal esophageal afferent neurons with 0.5% capsaicin in immature canines elicits an intense response referred to as the Esophago- Laryngeal Adductor Reflex (ELAR). The ELAR is characterized by hypertension, tachycardia and intense vocal cord adduction which progresses to laryngospasm. The ELAR demonstrates a unique age-dependency that bears important similarities with the age predisposition of apparent life-threatening events, and sudden infant death syndrome. The ELAR is absent in canines under 6 weeks of age, peaks in intensity between 7-19 weeks of age, and wanes with maturity. Previous studies have suggested that substance P is a key neurotransmitter of the ELAR and that the efferent limb of the response is vagally mediated. The afferent limb and the role of the central nervous system in the ELAR are unknown. This proposal further investigates the ELAR in immature canines. The specific objectives of the proposal are: 1. To characterize the response of the airway of immature canines to distal esophageal afferent stimulation. 2. To assess the effect of maturation on the cardiorespiratory and laryngeal responses of distal esophageal nociceptive stimulation 3. To elucidate the afferent neural pathway of the ELAR. 4. To determine the role of the central vagal nuclei in mediating the ELAR. 5. To determine if esophageal acidification induces the ELAR in immature canines with acute esophagitis. These specific aims will be explored in immature canines by applying 0.5% capsaicin to the distal esophageal mucosa to elicit an ELAR. The airway response of the ELAR (bronchoconstriction, change in respiratory rate, and laryngeal adduction) will be assessed. Esophageal stimulation with 0.5% capsaicin will be repeated every 3 weeks in 6 week old puppies for 15 weeks to characterize the effect of maturation on the intensity of the ELAR response. Transection and denuding studies will clarify the role of the vagus nerve in mediating the afferent limb of the ELAR. The role of the central vagal nuclei in mediating the ELAR will be assessed by comparing the response to distal esophageal nociceptive stimulation with capsaicin before and after chemically antagonizing their substance P NK1 receptors. Finally, the cardiorespiratory response following distal esophageal acidification of an acutely inflamed esophagus will be compared with the ELAR elicited by 0.5% capsaicin stimulation.

0.5%辣椒素对大鼠远端食道传入神经元的刺激作用 未成熟的犬类会引起一种被称为食道病的强烈反应-- 喉内收肌反射(ELAR)。Elar的特点是 高血压、心动过速和强烈的声带内收 发展为喉痉挛。 ELAR表现出一种独特的年龄依赖性，具有重要的 与明显危及生命的年龄倾向相似 事件，以及婴儿猝死综合症。犬类的舌尖不存在 在6周龄以下，强度在7-19周龄达到高峰，并且 会随着成熟而消退。 此前的研究表明，P物质是 极角的神经递质和反应的传出肢体 都是通过而来的。传入肢体与中枢的作用 Elar的神经系统是未知的。 这一建议进一步研究了未成熟犬的ELAR。这个 该提案的具体目标是： 1.研究未成熟犬的呼吸道反应。 远端食道传入刺激。 2.评价成熟度对心肺功能的影响 远端食道伤害性刺激的喉部反应 3.阐明ELAR的传入神经通路。 4.确定迷走神经中央核团在调节脑电活动中的作用。 埃拉尔。 5.确定食道酸化是否会诱发未成熟患者的ELAR 患有急性食管炎的犬只。 这些特定的目标将在未成熟的犬类身上进行探索，方法是将0.5% 辣椒素作用于远端食道粘膜，以引起食道远端粘膜的收缩。呼吸道 ELAR的反应(支气管收缩，呼吸频率改变， 和喉部内收)将被评估。食道刺激法 0.5%的辣椒素将在6周大的幼犬中每3周重复一次，用于 15周来表征成熟度对成熟度的影响 埃拉尔回应。横切和剥离研究将阐明 迷走神经与前角传入支的联系。的作用 中枢迷走神经核团在调节Elar中的作用将通过 食道远端伤害性刺激的反应比较 辣椒素对P物质NK1的化学拮抗作用 感受器。最后，远端的心肺反应。 急性发炎食道的食管酸化将是 与0.5%辣椒素刺激引起的ELAR相比。