Institute for Cell and Molecular Biosciences, The Medical School, Newcastle University, Framlington Place, Newcastle upon Tyne, United Kingdom.
Laryngoscope. 2010 Apr;120(4):777-82. doi: 10.1002/lary.20665.
OBJECTIVES/HYPOTHESIS: Exposure of pig laryngeal mucosa to pepsin and acid will have a differential damaging effect depending on the anatomical site, mirroring the effects seen in the human larynx in laryngopharyngeal reflux (LPR). This study aims to quantitate damage caused to laryngeal tissue by acid alone, and acid and pepsin, and also to determine if the extent of this damage depends on the tissue site.
Prospective translational research study.
An excised porcine laryngeal damage model in a small Ussing chamber was used to measure the effect of pepsin and acid on five sites (ventricles, vocal folds, posterior commissure, supraglottic, and subglottic mucosa). The tissue samples were incubated on the lumenal side for 1 hour with pH 2 and 4 HCl, pH 2 plus 1 mg/mL pepsin, and pH 4 plus 1 mg/mL pepsin. Damage was assessed by changes in absorbance of the bathing solution at optical density (OD) 260 nm and OD 280 nm and by measurement of released DNA compared to tissues bathed in pH 7.4 buffer. Damage was also assessed histologically.
Based on histology, all the tissues were resistant to pH 4.0 except the subglottic mucosa. Only the posterior commissure was not damaged by pH 2.0 plus pepsin. Similar patterns were observed with absorbance changes and DNA release.
The subglottic mucosa was the most susceptible to damage and the posterior commissure the least. Laryngeal tissues are essentially resistant to damage at pH 4.0, but are damaged when pepsin is present. This suggests that in LPR, pH 4.0 or above refluxate would only be damaging if it contains pepsin.
目的/假设：胃蛋白酶和酸暴露于猪喉黏膜将具有不同的损伤作用，这取决于解剖部位，反映了胃食管反流病（LPR）中喉的作用。本研究旨在定量分析酸单独、酸和胃蛋白酶对喉组织造成的损伤，以及确定这种损伤的程度是否取决于组织部位。
前瞻性转化研究。
在一个小型 Ussing 室中使用离体猪喉损伤模型来测量胃蛋白酶和酸对五个部位（喉室、声带、后连合、声门上区和声门下区）的影响。将组织样本在腔侧用 pH 2 和 4 HCl、pH 2 加 1mg/ml 胃蛋白酶和 pH 4 加 1mg/ml 胃蛋白酶孵育 1 小时。通过 260nm 和 280nm 光密度（OD）处的洗液吸光度变化以及与 pH 7.4 缓冲液孵育的组织相比释放的 DNA 来评估损伤。还通过组织学评估损伤。
根据组织学，除了声门下区外，所有组织均耐受 pH 4.0。只有后连合不受 pH 2.0 加胃蛋白酶的损伤。吸光度变化和 DNA 释放也观察到类似的模式。
声门下区最易受损，后连合最少受损。喉组织在 pH 4.0 时基本不受损伤，但当存在胃蛋白酶时会受损。这表明在 LPR 中，只有含有胃蛋白酶的 pH 4.0 或更高的反流物才会造成损伤。
