Department of Communication Sciences and Disorders, College of Allied Health Sciences, East Carolina University, 600 Moye Blvd., Greenville, NC 27858, USA.
Dysphagia. 2010 Jun;25(2):112-26. doi: 10.1007/s00455-009-9232-1. Epub 2009 Jun 3.
We recently established that the SOD1-G93A transgenic mouse is a suitable model for oral-stage dysphagia in amyotrophic lateral sclerosis (ALS). The purpose of the present study was to determine whether it could serve as a model for pharyngeal-stage dysphagia as well. Electrophysiological and histological experiments were conducted on end-stage SOD1-G93A transgenic mice (n = 9) and age-matched wild-type (WT) littermates (n = 12). Transgenic mice required a twofold higher stimulus frequency (40 Hz) applied to the superior laryngeal nerve (SLN) to evoke swallowing compared with WT controls (20 Hz); transgenic females required a significantly higher (P < 0.05) stimulus frequency applied to the SLN to evoke swallowing compared with transgenic males. Thus, both sexes demonstrated electrophysiological evidence of pharyngeal dysphagia but symptoms were more severe for females. Histological evidence of neurodegeneration (vacuoles) was identified throughout representative motor (nucleus ambiguus) and sensory (nucleus tractus solitarius) components of the pharyngeal stage of swallowing, suggesting that pharyngeal dysphagia in ALS may be attributed to both motor and sensory pathologies. Moreover, the results of this investigation suggest that sensory stimulation approaches may facilitate swallowing function in ALS.
我们最近证实，SOD1-G93A 转基因小鼠是肌萎缩侧索硬化症（ALS）口腔期吞咽困难的合适模型。本研究的目的是确定它是否也可以作为咽期吞咽困难的模型。对终末期 SOD1-G93A 转基因小鼠（n = 9）和年龄匹配的野生型（WT）同窝仔（n = 12）进行了电生理和组织学实验。与 WT 对照组（20 Hz）相比，转基因小鼠需要将喉上神经（SLN）的刺激频率提高两倍（40 Hz）才能诱发吞咽；与转基因雄性相比，转基因雌性需要更高（P < 0.05）的 SLN 刺激频率才能诱发吞咽。因此，两性均表现出咽期吞咽困难的电生理证据，但女性的症状更为严重。在咽期吞咽的代表性运动（疑核）和感觉（孤束核）成分中均发现了神经退行性变（空泡）的组织学证据，表明 ALS 中的咽期吞咽困难可能归因于运动和感觉病理学。此外，本研究的结果表明，感觉刺激方法可能有助于 ALS 中的吞咽功能。
