豚鼠外耳道加压对实验性膜迷路积水的影响

EFFECTS OF INTERMITTENT OVERPRESSURE IN EAR CANAL ON ENDOLYMPHATIC HYDROPS IN GUINEA PIGS

建立豚鼠外耳道间断加压模型 ,用常规火棉胶切片及免疫组化SP法研究外耳道 2 0cmH2 O间断加压对豚鼠膜迷路积水及耳蜗管外侧壁心钠素 (ANP)表达的影响。结果发现 ,2 0cmH2 O间断加压对中耳及内耳均无明显损伤 ;间断加压使膜迷路积水程度减轻 ,听反应阈无明显改变 ,加压使耳蜗管外侧壁ANP表达减弱。说明2 0cmH2 O的压力相对安全 ,间断加压可减慢膜迷路积水的发展 ,但对提高听功能无明显效果 ;

Intermittent overpressure of 20cmH 2 O was delivered to the external ear canal of guinea pigs. Histopathological changes in the middle and inner ear were examined under light microscope. Auditory evoked potential was recorded. The expression of atrial natriuretic peptide (ANP) was investigated by immunohistochemical SP method. We found that intermittent overpressure could minimize, but could not interrupt the development of endolymphatic hydrops,and could not improve hearing function. Expression of ANP decreased in the cochlear lateral wall after 2 week intermittent overpressure. The results suggested that intermittent overpressure of 20cmH 2 O was suitable in this experiment, and that ANP positive cells had an autocrine/paracrine function.