噪声暴露对大鼠ABR反应阈及听皮层谷氨酸脱羧酶67表达的影响

Changes of Auditory Brainstem Response and Expression of Glutamate Decarboxylase-67 in the Auditory Cortex in Rats Following Noise Exposure

刘芳利;罗彬;孙敬武;陈浩;

1:安徽医科大学附属安徽省立医院耳鼻咽喉头颈外科

摘要
目的研究噪声暴露对大鼠听性脑干反应(auditory brainstem response,ABR)及听皮层谷氨酸脱羧酶67(glutamic acid decarboxylase-67,GAD67)表达的影响。方法将21只健康雌性SD大鼠随机分为噪声暴露后0、7、14天组,每组7只,每组再随机分为对照组(3只)和暴露组(4只);将暴露组大鼠暴露于频率4kHz以上、100dB SPL白噪声2小时建立噪声性听觉损伤的动物模型,对照组大鼠不作任何处理;分别于噪声暴露前及暴露后0天(0.52小时)、第7天、第14天时检测各组大鼠的ABR反应阈;取噪声暴露后0天(22小时)、第7天、第14天时检测各组大鼠的ABR反应阈;取噪声暴露后0天(24小时)、第7天、第14天各组大鼠的听皮层切片,用免疫组织化学的方法标记各组听皮层中GAD67阳性神经元数量。结果①在噪声暴露后0.54小时)、第7天、第14天各组大鼠的听皮层切片,用免疫组织化学的方法标记各组听皮层中GAD67阳性神经元数量。结果①在噪声暴露后0.52小时暴露组大鼠的ABR反应阈明显高于对照组(P<0.05),14天时基本恢复正常;②在噪声暴露后22小时暴露组大鼠的ABR反应阈明显高于对照组(P<0.05),14天时基本恢复正常;②在噪声暴露后24小时暴露组大鼠听皮层GAD67阳性神经元数量(78.76±16.11个/mm2)明显多于对照组(38.43±9.27个/mm2)(P<0.05),第7天和第14天时暴露组GAD67阳性神经元数量(32.22±8.61个/mm2和29.55±11.61个/mm2)明显低于对照组(43.58±12.87个/mm2和43.14±12.44个/mm2)(均P<0.05)。结论噪声暴露使大鼠ABR反应阈发生了暂时性阈移,听皮层GAD67阳性神经元数量在噪声暴露后先增多后减少,可能与噪声性聋发病机制有关。
关键词
大鼠;噪声;听性脑干反应;听皮层;谷氨酸脱羧酶67
基金项目(Foundation):
国家自然科学基金(81200741);; 安徽省自然基金(11040606M174)资助
作者
刘芳利;罗彬;孙敬武;陈浩;
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