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目的：探讨神经生长因子（ｎｅｒｖｅ ｇｒｏｗ ｔｈ ｆａｃｔｏｒ，ＮＧＦ）对噪声性听力损伤的保护作用。方法：以听阈、耳蜗酶组织化学检测等为指标， 观察豚鼠每天在１１５ ｄＢ（Ａ）稳态噪声连续６ ｄ 的暴露（４５ ｍ ｉｎ／ｄ）前，肌肉注射不同剂量的ＮＧＦ对豚鼠皮层声诱发电位、听毛细胞琥珀酸脱氢酶（ｓｕｃｃｉｎｉｃ ｄｅｈｙｄｒｏｇｅｎａｓｅ， ＳＤＨ）活性的影响。结果：Ａ［ＮＧＦ：１ ０００ ＢＵ／（ｋｇ·ｄ），ｉｍ ．］， Ｂ［ＮＧＦ：２ ０００ ＢＵ／（ｋｇ·ｄ），ｉｍ ．］和Ｃ［ＮＧＦ：３ ０００ ＢＵ／（ｋｇ·ｄ），ｉｍ ．］３ 个实验组动物听阈偏移幅度均小于对照组［生理盐水：１ ｍ ｌ／（ｋｇ·ｄ），ｉｍ ．］，相差非常显著；实验Ｂ，Ｃ两组动物在噪声暴露后第３天听阈已基本恢复，而对照组动物在噪声暴露后第６天仍有（１６．４３±６．９１） ｄＢ的阈移。３ 个实验组耳蜗毛细胞ＳＤＨ 活性减弱程度也比对照组明显为轻； 而实验Ｂ，Ｃ两组则无显著性差异，但它们又明显轻于实验Ａ 组。结论：ＮＧＦ能减轻噪声对耳蜗及神经的损害，对听觉功能具有明显的保护作用。
Objective: To investigate the protective effect of nerve growth factor (NGF) on noise-induced hearing impairment. Methods: The auditory threshold and cochlear histochemistry were used as indexes to observe the effect of different doses of NGF on guinea pig cortical sound before guinea pigs exposed to 115 dB (A) steady state noise for 45 consecutive days (45 mins / d) Evoked potentials, listening hair cells succinate dehydrogenase (succinic dehydrogenase, SDH) activity. Results: A [NGF: 1 000 BU / (kg · d), im. ], B [NGF: 2 000 BU / (kg · d), im. ] And C [NGF: 3 000 BU / (kg · d), im. The amplitude of auditory threshold deviation of the three experimental groups was less than that of the control group [saline: 1 m l / (kg · d), im. ], The difference was very significant. In the experimental group B and C, the hearing threshold of the animals in the three days after the noise exposure basically recovered, while the control animals still had the threshold of (16.43 ± 6.91) dB on the sixth day after the noise exposure shift. The degeneration of SDH activity of cochlear hair cells in the three experimental groups was also significantly lower than that in the control group. However, there was no significant difference between the experimental groups B and C, but they were obviously lighter than the experimental group A. Conclusion: NGF can reduce the damage of noise to cochlear and nerve and has obvious protective effect on auditory function.