摘要
目的前期研究表明急性及慢性注射水杨酸钠可致豚鼠畸变产物耳声发射(distortion productot oacoustic emissions,DPOAE)幅值可逆性改变。本研究通过对急性及慢性水杨酸钠肌注后,大鼠耳蜗prestin基因mRNA及其蛋白表达的检测,探讨其引起DPOAE幅值改变的可能机制。方法实验动物随机分为慢性组、急性组、慢性恢复组、正常对照组。各组大鼠断头处死后迅速剥离耳蜗;采用基于Taqman探针的荧光实时定量逆转录聚合酶链反应(real-time reverse transcriptase polymerase chain reaction,real-time RT-PCR)及Western blot(蛋白质印迹)方法,检测各组大鼠耳蜗prestin基因mRNA及其蛋白的表达变化。结果 (1)慢性组prestin基因mRNA及其蛋白表达水平较正常组高,差异有显著性(P<0.05),其中mRNA上调2.25倍;(2)急性水杨酸钠注射组prestin基因mRNA及其蛋白表达量水平与正常对照组无显著性差异(P>0.05);(3)慢性注射水杨酸钠后恢复28天,大鼠耳蜗中prestin基因mRNA及其蛋白表达水平与正常对照组无显著性差异(P>0.05)。结论 (1)急性注射水杨酸钠对耳蜗prestin基因的表达无影响;(2)长期注射水杨酸钠使耳蜗prestin基因表达可逆性上调可能是其引起DPOAE幅值增加的主要原因,推测水杨酸钠致耳鸣极可能起源于OHC水平,为水杨酸钠致耳鸣的机制提供了重要的实验依据。
Objective Our previous study demonstrated that acute and chronic administration of salicylate reversibly changed the amplitude of distortion product of otoacoustic emissions（DPOAE）,which are mainly contributed by OHC electromotility.To explore the underlying mechanisms of these changes,experiments were explored to investigate the different expression of prestin in rat cochlear induced by acute and chronic sodium salicylate injection.Methods Rats were randomly divided into four groups（chronic sodium salicylate injections,acute sodium salicylate injections,chronically injections with recovery period and normal rats）.Taqman real-time reverse transcriptase polymerase chain reaction（realtime RT-PCR） and Western blot was used to study the different expression of prestin mRNA and protein levels in the four groups.Results As compared with that of normal control group,the expression of prestin mRNA and protein level in chronic sodium salicylate injected group was significantly increased（P 0.05）,of which the mRNA level is 2.25 fold than normal group;There are no significant changes among the chronically injections with recovery period,normal control group and acute sodium salicylate injected group（P 0.05）.Conclusions Acute salicylate injection decreases the DPOAE amplitude not through changing the prestin expression way.Chronic salicylate administration markedly,but reversibly,increased the prestin gene and protein levels which may contribute to the enhanced DPOAE amplitudes.These changes in prestin expression may be one mechanism by which salicylate can induce tinnitus at the OHC level.
出处
《中华耳科学杂志》
CSCD
2010年第4期451-455,共5页
Chinese Journal of Otology
基金
国家自然科学基金项目(No.30973298)
