维生素E对短期噪声暴露引起豚鼠听力损失的预防作用

目的研究维生素E对噪声性听力损失是否具有预防作用。方法48只雄性花色豚鼠随机分为6组,每组8只。1、2、3、4组进行中心频率为4kHz、强度为100dB(A)的倍频程噪声暴露,8h/d,连续3d;于噪声暴露前3d、噪声暴露的每一天及噪声暴露后3d,分别腹腔注射生理盐水、玉米油、10.0mg/kg维生素E、50.0mg/kg维生素E,1次/d,连续9d;5、6组不接受噪声暴露,分别腹腔注射生理盐水、50.0mg/kg的维生素E,注射时间同噪声暴露组。比较噪声暴露后即刻及2、8d,各组豚鼠听觉脑干反应(ABR)阈移,评价维生素E对噪声性听力损失的预防作用。结果第3组豚鼠在噪声暴露后即刻及2、8d,在2、4、8kHz处的ABR阈移分别为(15.9±6.8)、(39.4±4.8)、(42.5±6.3)、(0.3±2.5)、(19.1±7.9)、(21.9±6.4)、(0.3±1.6)、(10.9±8.6)、(12.2±8.1)dB,明显低于第1组豚鼠在噪声暴露后即刻及2、8d,在2、4、8kHz处的ABR阈移分别为(30.9±11.3)、(47.8±8.8)、(49.7±6.9)、(10.0±3.5)、(29.1±6.5)、(29.1±7.6)、(4.7±3.6)、(20.3±6.5)、(17.5±9.0)dB],差异有统计学意义(P<0.05)。第4组豚鼠在噪声暴露后即刻及2、8d,在2、4、8kHz处的ABR阈移分别为(14.4±5.3)、(36.6±4.4)、(43.1±2.9)、(0.3±2.5)、(16.9±4.6)、(19.4±3.2)、(0.0±3.7)、(7.5±4.2)、(9.1±4.2)dB,明显低于第1组豚鼠在噪声暴露后即刻及2、8d,在2、4、8kHz处的ABR阈移,差异亦有统计学意义(P<0.05)。结论维生素E具有一定的预防噪声性听力损失的作用。

Preventive effects of vitamin E on short-term noise-induced hearing loss in guinea pigs

OBJECTIVE: To study the preventive effects of vitamin E on short-term noise-induced hearing loss (NIHL). METHODS: Forty-eight male pigmented guinea pigs were randomly divided into 6 groups, 8 animals in each group. The animals of group 1, 2, 3, 4 were exposed to the noise (4 kHz octave band noise, 100 dB SPL), 8 hours per day for 3 days consecutively and received normal saline, corn oil, 10 mg/kg vitamin E, 50 mg/kg vitamin E respectively daily by intraperitoneal injection from 3 days before the noise exposure, through the 3 noise exposure days to 3 days after the noise exposure. The animals of group 5 and group 6 days were not exposed to the noise but received normal saline and 50 mg/kg vitamin E injection respectively at the same time as that of group 1, 2, 3, 4. The preventive effects of vitamin E on NIHL were determined by comparing the threshold shifts of auditory brainstem responses (ABR) immediately, on the second day and on the 8th day after the exposure. RESULTS: The ABR threshold shifts immediately, on the second day and on the 8th day after the exposure for group 3 at 2, 4 and 8 kHz were (15.9 +/- 6.8), (39.4 +/- 4.8), (42.5 +/- 6.3), (0.3 +/- 2.5), (19.1 +/- 7.9), (21.9 +/- 6.4), (0.3 +/- 1.6), (10.9 +/- 8.6), (12.2 +/- 8.1) dB, respectively, which were significantly lower than those for group 1 (30.9 +/- 11.3), (47.8 +/- 8.8), (49.7 +/- 6.9), (10.0 +/- 3.5), (29.1 +/- 6.5), (29.1 +/- 7.6), (4.7 +/- 3.6), (20.3 +/- 6.5), (17.5 +/- 9.0) dB, respectively] (P < 0.05). The ABR threshold shifts immediately, on the second day and on the 8th day after the exposure for group 4 at 2, 4 and 8 kHz were respectively (14.4 +/- 5.3), (36.6 +/- 4.4), (43.1 +/- 2.9), (0.3 +/- 2.5), (16.9 +/- 4.6), (19.4 +/- 3.2), (0.0 +/- 3.7), (7.5 +/- 4.2), (9.1 +/- 4.2) dB, which were significantly lower than those for group 1 (P < 0.05). CONCLUSION: Vitamin E has some preventive effects on the NIHL.