不同强度噪声对豚鼠耳蜗HSP70表达特点的影响

目的 ]观察无损伤的中等强度的习服声刺激后耳蜗中热应激蛋白 (heatshockprotein ,HSP)的表达特点。 方法 ]习服组先接受 10d每天 6h习服声暴露 ;对照组静置饲养 10d ;习服 +高噪声暴露组先接受 10d每天 6h习服声暴露 ,休息 2d后 ,再暴露于高强度噪声 2h ;高噪声暴露组直接暴露于高强度噪声 2h。然后以免疫组织化学方法结合图像分析技术检测各组动物耳蜗HSP70表达情况。 结果 ]习服组耳蜗中HSP70 (积分光密度为 2 2 .99,平均光密度为 0 .2 8)明显高于对照组 (积分光密度为 6.77,平均光密度为 0 .11) (P <0 .0 5 ) ;习服 +高噪声组明显低于高噪声暴露组 (P <0 .0 5 ) ,两组积分光密度分别为 2 0 .0 6和 43 .14 ,平均光度分别为 0 .3 0和 0 .40。 结论 ]用无损伤的中等强度习服声诱导耳蜗中HSP70的表达高于正常状态时的表达而低于高强度噪声刺激时的表达 ,但习服过程诱导产生的HSP70却对听觉系统提供了一定的保护作用

Study on the Expression Characteristic of HSP70 in Cochlea of Guinea Pigs by Different Intensity of Noise

Objective To observe the expression characteristic of heat shock protein 70(HSP70) in Corti's organ of guinea pigs after low level sound conditioning.Methods] Conditioning group was exposed to low level noise,6 hours a day for 10 days;control group was placed in a quiet environment;conditioning plus high level group was first exposed to low level noise,6 hours a day for 10 days,then to high level noise for 2 hours;high level group was exposed to high level noise for 2 hours only.The expression of HSP70 in guinea pigs cochleae after exposure to noise were examined by immunohistochemistry and image analysis system.Results] The expression of HSP70 in conditioning group showed a significant increase compared with that in control group(P<0.05). The expression of HSP70 in conditioning plus high level group showed a significant reduction compared with that in high level group(P<0.05). Conclusion] HSP70 in Corti's organ induced by low level sound conditioning is higher than that in normal Corti's organ,and lower than that induced by high level noise stimulus. But HSP70 in Corti's organ induced by low level sound conditioning might provide protective effect on auditory system.