Implementation of a method to visualize noise-induced hearing loss in mass stranded cetaceans.
Implementation of a method to visualize noise-induced hearing loss in mass stranded cetaceans.
复制标题
DOI：
10.1038/srep41848
复制
发表时间：
2017-02-06
影响因子：
4.6
通讯作者：
André M
中科院分区：
文献类型：
--
作者：
Morell M;Brownlow A;McGovern B;Raverty SA;Shadwick RE;André M
评估搁浅鲸类过度暴露于噪音的影响具有挑战性，因为导致听力损失的病变发生在细胞水平，而内耳细胞对自溶非常敏感。区分生前病理和死后变化一直是诊断潜在影响的主要限制。在这里，我们概述了一种适用于检测搁浅鲸类动物噪声引起的听力损失的方法。从苏格兰的两个大规模搁浅的长鳍领航鲸的内耳进行扫描电子显微镜观察。在一个案例中，一只幼年动物的耳朵在死亡后4小时内被固定，发现耳蜗螺旋顶端的许多感觉细胞缺失。在这种情况下，外毛细胞的缺失将与过度暴露于水下噪音相适应，从而影响转换领航鲸听力频谱最低频率的区域。用固定剂灌注耳蜗大大改善了保存，甚至在死亡后30小时也能对Corti器官进行诊断成像。这一发现支持通过一个常规的协议，以检测噪声过度的病理遗产在大规模搁浅鲸类动物作为一个关键，了解复杂的过程和影响，背后的搁浅事件。
Assessment of the impact of noise over-exposure in stranded cetaceans is challenging, as the lesions that lead to hearing loss occur at the cellular level and inner ear cells are very sensitive to autolysis. Distinguishing ante-mortem pathology from post-mortem change has been a major constraint in diagnosing potential impact. Here, we outline a methodology applicable to the detection of noise-induced hearing loss in stranded cetaceans. Inner ears from two mass strandings of long-finned pilot whales in Scotland were processed for scanning electron microscopy observation. In one case, a juvenile animal, whose ears were fixed within 4 hours of death, revealed that many sensory cells at the apex of the cochlear spiral were missing. In this case, the absence of outer hair cells would be compatible with overexposure to underwater noise, affecting the region which transduces the lowest frequencies of the pilot whales hearing spectrum. Perfusion of cochlea with fixative greatly improved preservation and enabled diagnostic imaging of the organ of Corti, even 30 hours after death. This finding supports adopting a routine protocol to detect the pathological legacy of noise overexposure in mass stranded cetaceans as a key to understanding the complex processes and implications that lie behind such stranding events.