内耳蛋白质有助于医生治疗听力问题

法国研究者称，内耳耳蜗内有一种蛋白质可以帮助人们分辨声音、理解谈话内容，这一研究结果有助于治疗听力障碍患者。

法国克莱蒙费朗大学（University of Auvergne in Clermont-Ferrand）的研究员Paul Avan在接受电话采访时说，该研究还有助于解释，为什麽有的人在拥挤的饭店或其他噪声大的环境中会听不清楚。

研究者使用经基因工程技术培育的老鼠做实验，观察老鼠内耳的耳蜗部位。耳蜗里有两种探测声音的听觉细胞。

目前普遍认为，听觉细胞内的“离子通道”（ion channel）起到在内耳扭曲声音的作用。离子通道好比麦克风，能将声音转化成电信号传递给大脑。声音“扭曲”後，人们可以从噪音中分辨出声音来源的背景是什麽，找到自己想要的声音。

而Avan说，研究者发现，让听觉细胞保持完整、使得声音在内耳发生恰当的失真效果的，是一种叫做stereocilin的蛋白质，而不是传统认为的离子通道。

借助此项研究成果，医生可以诊断出患者更细微的听力问题，并提供更有针对性的帮助措施，消除从某些方向传来的噪音。

来源：http://www.reuters.com/article/healthNews/idUSTRE4978SH20081009?sp=true

A protein in the inner ear helps people differentiate between sounds and understand speech, French researchers reported on Wednesday in a finding that could help treat the hard of hearing.

The study also helps explain why some people have difficulty hearing in crowded restaurants or other noisy places, said Paul Avan, a researcher at the University of Auvergne in Clermont-Ferrand, France.

"This won't help cure deafness but will help diagnose why some people have hearing problems, especially in noisy places," Avan, who worked on the study, said in a telephone interview.

The study, which used genetically engineered mice, looked at the part of the inner ear called the cochlea, which contains two types of sensory cells to detect sounds.

Scientists often study mice because of the biological similarities between the animals and humans.

Until now people had thought that structures called ion channels found in the cells -- which work like a microphone to transform sound into electrical messages to the brain -- were mainly responsible for distorting sound in the inner ear.

Distortion is important because it allows people to pick out the correct sounds from a mixture of noises whether it be competing conversations at a cocktail party or other kinds of background noise, Avan said.

But the researchers showed how a protein called stereocilin -- not the ion channels -- was keeping sensory cells intact and allowing the inner ear to properly distort sounds, Avan said.

Mice without stereocilin did not hear properly even when their ion channels worked, Avan and colleagues reported in the journal Nature.

The findings could help doctors diagnose more subtle hearing problems and fit certain people with special hearing aids that eliminate noise coming from certain directions, Avan said.

"Until now it was thought that if the ion channels worked everything would be okay," Avan said. "We show that this is not the case. Sensitivity will be good but that does nothing if you don't understand anything if it is noisy around you."

TAG: 蛋白质 内耳 听力 医生 治疗