Instituto Superior de Ciências da Saúde Egas Moniz, CiiEM, Almada, Portugal.
Clin Res Hepatol Gastroenterol. 2012 Feb;36(1):72-7. doi: 10.1016/j.clinre.2011.10.002. Epub 2011 Nov 21.
Non-auditory effects of noise, including digestive disorders have long being reported. Low frequency noise (LFN) is considered to be responsible to most of non-auditory effects of noise and is widely spread in modern societies. Only a few studies were designed to evaluate these noise-induced digestive alterations. The pathogenesis of duodenal ulcers and erosions is complex and noise may be an environmental co-factor. The aim of the present study was to investigate the morphological injury of LFN-exposed duodenal mucosa.
Five groups of Wistar rats were exposed to continuous LFN, during increasing periods, since 1 to 13 weeks. A control group was kept in silence. Duodenal specimens were studied using light microscopy (LM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM).
We disclosed several changes in LFN-exposed rats: on LM, mucosa showed superficial erosions of the epithelial layer, degeneration, picnosis and cell death, with no inflammation. On SEM, epithelium presented displacement of cells and unequal distribution of microvilli, with coalescence and fusion. On TEM, microvilli were irregularly distributed, damaged and fragmented. The terminal web was destroyed. Morphological alterations occurred early, after just 1 week of LFN-exposure, persisted with longer noise exposition and did not suffer any evolution. Changes were similar among all LFN-exposed groups.
LFN-exposed duodenal mucosa develops destruction of microvilli and terminal web, leading to cellular death and development of superficial erosions. These lesions of cytoskeleton structures could explain why cells with actinic and tubulinic structures like cilia and microvilli present severe destruction after LFN-exposure. These erosions are similar to those seen in dyspeptic patients.
噪声的非听觉效应，包括消化紊乱，早已被报道。低频噪声（LFN）被认为是噪声的大多数非听觉效应的原因，并且广泛存在于现代社会中。只有少数研究旨在评估这些噪声引起的消化变化。十二指肠溃疡和糜烂的发病机制很复杂，噪声可能是环境的协同因素。本研究的目的是研究 LFN 暴露引起的十二指肠黏膜形态损伤。
五组 Wistar 大鼠连续暴露于 LFN 中，时间从 1 周到 13 周不等。一组对照组保持安静。使用光镜（LM）、扫描电子显微镜（SEM）和透射电子显微镜（TEM）研究十二指肠标本。
我们在 LFN 暴露的大鼠中发现了几种变化：在 LM 上，黏膜显示上皮层的浅表糜烂、变性、萎缩和细胞死亡，但没有炎症。在 SEM 上，上皮细胞出现细胞位移和微绒毛分布不均匀，融合和融合。在 TEM 上，微绒毛分布不规则，受损和碎片化。终末网被破坏。形态改变发生较早，仅在 LFN 暴露 1 周后，随着噪声暴露时间的延长而持续存在，且没有任何演变。所有 LFN 暴露组的变化均相似。
LFN 暴露的十二指肠黏膜会发生微绒毛和终末网的破坏，导致细胞死亡和浅表糜烂的发展。这些细胞骨架结构的损伤可能解释了为什么像纤毛和微绒毛这样具有肌动蛋白和微管结构的细胞在 LFN 暴露后会受到严重破坏。这些糜烂类似于消化不良患者的糜烂。
