Department of Otolaryngology-Head and Neck Surgery, Beijing Tongren Hospital, Capital Medical University, Beijing, China.
Key Laboratory of Otolaryngology Head and Neck Surgery, Ministry of Education, Capital Medical University, Beijing, China.
Laryngoscope. 2021 Apr;131(4):E1256-E1264. doi: 10.1002/lary.29210. Epub 2020 Oct 24.
OBJECTIVES/HYPOTHESIS: The present study investigated the characteristics of early internal laryngeal muscle atrophy in recurrent laryngeal nerve injury (RLNI) rats.
To observe the characteristics of early internal laryngeal muscle atrophy post RLNI.
Rats were divided into three groups: sham-operated control group (n = 20), recurrent laryngeal nerve transverse injury group (RLNTI, n = 50), and recurrent laryngeal nerve blunt contusion group (RLNBC, n = 50). Five weeks after RLNI, certain rats were sacrificed weekly, and their laryngeal tissues were harvested. The atrophic features of internal laryngeal muscles were detected using hematoxylin and eosin. NF-κB and MuRF-1 levels were tested using IHC.
The atrophic degree and fibrosis of thyroarytenoid, posterior cricoarytenoid, and lateral cricoarytenoid muscles were related to the type of RLNI. The average myofiber cross-sectional areas increased before an obvious decrease in the RLNTI and RLNBC groups. Muscle recovery occurred in the RLNBC group starting 4 weeks after RLNI, but only a weak trend was observed in the RLNTI group in the 5th week. During the muscle atrophy process, MuRF-1 and NF-κB were upregulated early and were maintained at a high level, which showed a trend similar to muscle atrophy. However, NF-κB expression was opposite to MuRF-1 expression and muscle atrophy when the muscles recovered.
The atrophy degree of internal laryngeal muscles was associated with the type of RLNI. The NF-κB/MuRF-1 signaling pathway was involved in internal laryngeal muscle atrophy after RLNI, which is different from skeletal muscle after denervation.
NA Laryngoscope, 131:E1256-E1264, 2021.
目的/假设：本研究旨在探讨喉返神经损伤（RLNI）后早期喉内肌萎缩的特征。
观察 RLNI 后早期喉内肌萎缩的特征。
将大鼠分为三组：假手术对照组（n = 20）、喉返神经横断损伤组（RLNTI，n = 50）和喉返神经钝挫伤组（RLNBC，n = 50）。RLNI 后 5 周，每周处死部分大鼠，采集其喉组织。使用苏木精和伊红（HE）染色检测内收肌萎缩特征。免疫组化（IHC）检测 NF-κB 和 MuRF-1 水平。
RLNI 类型与甲杓肌、环杓后肌和环杓侧肌的萎缩程度和纤维化有关。在 RLNTI 和 RLNBC 组，平均肌纤维横截面积在明显减少之前先增加。RLNBC 组在 RLNI 后 4 周开始出现肌肉恢复，但 RLNTI 组在第 5 周仅出现微弱趋势。在肌肉萎缩过程中，MuRF-1 和 NF-κB 早期上调并维持在较高水平，与肌肉萎缩呈相似趋势。然而，当肌肉恢复时，NF-κB 表达与 MuRF-1 表达和肌肉萎缩相反。
喉内肌的萎缩程度与 RLNI 的类型有关。NF-κB/MuRF-1 信号通路参与了 RLNI 后喉内肌萎缩，与去神经后骨骼肌不同。
无 喉科学杂志，131：E1256-E1264，2021。
