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本文利用激光多普勒血流计测量了不同频率的噪声暴露和不同暴露时间对豚鼠耳蜗血流的影响。结果表明１２０ｄＢ纯音暴露５或３０ｍｉｎ可引起耳蜗血流的显著降低，而１２０、１１０ｄＢ的低频噪声暴露对耳蜗血流无明显影响。３０分钟暴露的动物在声暴露停止后３０ｍｉｎ内尚未恢复到基础水平，而５分钟暴露组，在声暴露停止后数分钟内恢复到正常水平。切断同侧颈交感神经能减少噪声引起的耳蜗血流下降。在相同的强度下，低频噪声引起的阈移小，高频噪声引起的阈移大。结果提示耳蜗血流下降是声损伤的重要原因之一，交感神经在噪声引起的耳蜗血流下降中起一定的作用。
In this paper, laser Doppler flowmeters were used to measure the effects of different frequencies of noise exposure and different exposure time on cochlear blood flow in guinea pigs. The results showed that 120dB pure tone exposure for 5 or 30 min caused a significant decrease in cochlear blood flow, while 120,110 dB low frequency noise exposure had no significant effect on cochlear blood flow. Animals exposed for 30 minutes had not returned to basal level within 30 min of sonicated exposure, whereas the 5-minute exposed group returned to normal within minutes after sonicated exposure ceased. Cut off the ipsilateral cervical sympathectomy can reduce noise-induced cochlear blood flow decline. Under the same intensity, the threshold shift caused by low frequency noise is small and the threshold shift caused by high frequency noise is large. The results suggest that decreased blood flow in the cochlea is one of the important causes of acoustic damage. Sympathetic nerves play a role in the reduction of noise-induced cochlear blood flow.