Department of Occupational and Environmental Health, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, Aichi, 466-8550, Japan.
Environ Health Prev Med. 2019 Jun 1;24(1):39. doi: 10.1186/s12199-019-0794-8.
Cervical vestibular evoked myogenic potential (cVEMP) testing is a strong tool that enables objective determination of balance functions in humans. However, it remains unknown whether cVEMP correctly expresses vestibular disorder in mice.
In this study, correlations of cVEMP with scores for balance-related behavior tests including rotarod, beam, and air-righting reflex tests were determined in ICR mice with vestibular disorder induced by 3,3'-iminodipropiontrile (IDPN) as a mouse model of vestibular disorder.
Male ICR mice at 4 weeks of age were orally administered IDPN in saline (28 mmol/kg body weight) once. Rotarod, beam crossing, and air-righting reflex tests were performed before and 3-4 days after oral exposure one time to IDPN to determine balance functions. The saccule and utricles were labeled with fluorescein phalloidin. cVEMP measurements were performed for mice in the control and IDPN groups. Finally, the correlations between the scores of behavior tests and the amplitude or latency of cVEMP were determined with Spearman's rank correlation coefficient. Two-tailed Student's t test and Welch's t test were used to determine a significant difference between the two groups. A difference with p < 0.05 was considered to indicate statistical significance.
After oral administration of IDPN at 28 mmol/kg, scores of the rotarod, beam, and air-righting reflex tests in the IDPN group were significantly lower than those in the control group. The numbers of hair cells in the saccule, utricle, and cupula were decreased in the IDPN group. cVEMP in the IDPN group was significantly decreased in amplitude and increased in latency compared to those in the control group. cVEMP amplitude had significant correlations with the numbers of hair cells as well as scores for all of the behavior tests in mice.
This study demonstrated impaired cVEMP and correlations of cVEMP with imbalance determined by behavior tests in a mouse model of vestibular disorder.
颈源性前庭诱发肌源性电位(cVEMP)测试是一种强大的工具,可使人类的平衡功能得到客观的确定。然而,目前尚不清楚 cVEMP 是否能正确表达小鼠的前庭障碍。
本研究旨在通过 3,3'-亚氨基二丙腈(IDPN)诱导的前庭障碍小鼠模型,确定 cVEMP 与包括转棒、平衡木和空中翻正反射在内的平衡相关行为测试评分之间的相关性。
4 周龄雄性 ICR 小鼠口服给予 IDPN(28mmol/kg 体重)生理盐水溶液一次。在口服 IDPN 一次后 3-4 天,进行转棒、平衡木和空中翻正反射测试,以确定平衡功能。使用荧光鬼笔环肽标记球囊和椭圆囊。对对照组和 IDPN 组的小鼠进行 cVEMP 测量。最后,使用 Spearman 秩相关系数确定行为测试评分与 cVEMP 幅度或潜伏期之间的相关性。使用双尾学生 t 检验和 Welch t 检验确定两组之间的差异是否有统计学意义。p<0.05 差异被认为具有统计学意义。
口服 28mmol/kg 的 IDPN 后,IDPN 组的转棒、平衡木和空中翻正反射测试评分明显低于对照组。IDPN 组的球囊、椭圆囊和帽状纤维中的毛细胞数量减少。与对照组相比,IDPN 组的 cVEMP 幅度降低,潜伏期延长。cVEMP 幅度与小鼠所有行为测试的评分以及毛细胞数量均有显著相关性。
本研究表明,在前庭障碍小鼠模型中,cVEMP 受损,cVEMP 与行为测试确定的失衡之间存在相关性。