Respiratory activities of intrinsic tongue muscles

舌固有肌的呼吸活动

• 批准号: 6770984
• 负责人: E. FIONA BAILEY
• 金额: $ 7.58万
• 依托单位: UNIVERSITY OF ARIZONA
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-08-15 至 2005-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6770984
• 关键词: chemoreceptors; denervation; electromyography; hypercapnia; hypoxia; laboratory rat; male; mechanoreceptors; muscle function; pulmonary respiration; respiratory airway volume; tongue; tracheotomy

DESCRIPTION (provided by applicant): Tongue movement depends on the actions of both intrinsic (origin and insertion in the tongue) and extrinsic (attached to bone and inserted into the tongue) muscles. These muscles play a key role in swallowing, breathing, chewing, and speaking. Contraction of the extrinsic muscles is generally considered to change tongue position (protrusion or retrusion), whereas contraction of the intrinsic tongue muscles changes tongue shape. To date, research that examines the respiratory-related effects of tongue function in mammals has focused exclusively on the respiratory control and function of the extrinsic tongue muscles. The respiratory-related control and function of the intrinsic tongue muscles and their bearing on extrinsic tongue muscle activity are still unknown. Recent findings indicate that the intrinsic tongue muscles may contribute to tongue protrusion and retraction, and facilitate the actions of the extrinsic tongue muscles in swallowing. In light of these findings, our objective is to characterize the respiratory-related activities of the intrinsic tongue muscles in vivo. The specific goals of the present application are to test the following hypotheses: (1) intrinsic tongue muscles are co-activated with extrinsic tongue muscles during resting tidal breathing; (2) intrinsic and extrinsic tongue muscle activities are modulated in parallel by central and peripheral chemoreceptors and airway mechanoreceptors; and (3) the EMG of intrinsic and extrinsic tongue muscles exhibit similar onset times and burst characteristics during perturbations of chemoreceptor and mechanoreceptor feedback. Experiments will be conducted on urethane anesthetized, spontaneously breathing male Sprague-Dawley rats. Simultaneous EMG recordings of the hyoglossus, internal intercostal muscles and superior longitudinal muscles will be obtained under each of the following conditions: (1) hypoxia, hypercapnia, and asphyxia, to assess the effects of central and peripheral chemoreceptor stimulation of intrinsic tongue muscle activities; (2) before and after superior laryngeal nerve section, and before and after lingual nerve section, to quantify the influence of upper airway mechanosensory modulation of intrinsic tongue muscle activities; (3) with and without single-breath airway occlusion, to quantify the influence of phasic lung volume changes on drive to intrinsic tongue musculature. The results of this work will enhance our understanding of the functions of the tongue musculature and provide broad insights into the modulation of tongue muscle activities in breathing and other behaviors such as chewing and swallowing.

描述（由申请人提供）：舌的运动依赖于内在（起源于舌内并插入舌内）和外在（附着于骨并插入舌内）肌肉的作用。这些肌肉在吞咽、呼吸、咀嚼和说话中起着关键作用。外在肌肉的收缩通常被认为会改变舌头的位置（突出或向后），而内在肌肉的收缩则会改变舌头的形状。迄今为止，有关哺乳动物舌功能呼吸相关影响的研究都集中在舌外肌的呼吸控制和功能上。舌内肌的呼吸相关控制和功能及其对舌外肌活动的影响尚不清楚。