豚鼠去大脑僵直后畸变产物耳声发射变化的实验观察

DPOAEs amplitude decline after decerebration in guinea pigs

目的 :进一步确定皮层高级中枢是否对耳蜗主动微机制有调控作用。方法 :观察 17只豚鼠在去大脑僵直前、后的畸变产物耳声发射 (DPOAEs)变化情况。结果 :在避免体温和颅温下降、缺氧等情况下 ,豚鼠去大脑僵直后 2min、5min、10min的DPOAEs幅值显著下降 ,30min开始逐渐恢复 ,6 0min基本恢复到术前水平。结论 :结果提示大脑皮层高级中枢对耳蜗主动微机制有下行调控作用。

Objective:To further prove whether auditory cortex topdown efferent exists and observe its effect on outer hair cells (OHCs). Methods:Distortion product otoacoustic emissions (DPOAEs) were measured before and after decerebration in 17 guinea pigs. Results:DPOAEs amplitude decreased significantly and rapidly after decerebration and remained at the lowest levels for 2,5,10 min. DPOAEs gradually recovered to the previous levels with time delay. Conclusion:It was further demonstrated that auditory cortex efferent really exists and controls OHCs and DPOAEs via medial olivocochlear system (MOCS). The possible mechanism was discussed in the paper.