Bauman N M, Sandler A D, Schmidt C, Maher J W, Smith R J
Department of Otolaryngology, Head and Neck Surgery, University of Iowa Hospital and Clinics, Iowa City 52242.
Laryngoscope. 1994 Feb;104(2):209-14. doi: 10.1288/00005537-199402000-00015.
Distal esophageal sensory nerves were stimulated in 17 anesthetized dogs divided into three age groups to determine the laryngeal, cardiovascular, and respiratory effects. Group I puppies were 5 to 6 weeks of age, group II puppies were 8 to 19 weeks of age, and group III animals were adult dogs. Marked laryngeal adductor activity and laryngospasm were observed in group II puppies, while no or minimal laryngeal adduction was seen in younger puppies and adult dogs. Mean arterial pressure and heart rate increased significantly in groups II and III (P < .005) but remained unchanged in group I animals (P > .4). This response is distinctly different from the laryngeal chemoreflex because central apnea, hypotension, and bradycardia were absent. The afferent limb of the response is mediated by the vagus nerve as bilateral transthoracic truncal vagotomy eliminated the reflex. The laryngeal response observed following stimulation of distal esophageal afferent fibers may be important in the mechanism of apparent life-threatening events (ALTEs) and the sudden infant death syndrome (SIDS) associated with gastroesophageal reflux disease.
在17只麻醉犬中刺激食管远端感觉神经，这些犬被分为三个年龄组，以确定对喉部、心血管和呼吸的影响。第一组幼犬为5至6周龄，第二组幼犬为8至19周龄，第三组动物为成年犬。在第二组幼犬中观察到明显的喉内收肌活动和喉痉挛，而在较年幼的幼犬和成年犬中未见或仅有轻微的喉内收。第二组和第三组的平均动脉压和心率显著升高（P < .005），而第一组动物则保持不变（P > .4）。这种反应与喉化学反射明显不同，因为没有中枢性呼吸暂停、低血压和心动过缓。该反应的传入支由迷走神经介导，因为双侧经胸迷走神经切断术消除了该反射。刺激食管远端传入纤维后观察到的喉部反应可能在与胃食管反流病相关的明显危及生命事件（ALTEs）和婴儿猝死综合征（SIDS）的机制中起重要作用。
