Departament de Ciències Fisiològiques, Institut de Neurociènces, Universitat de Barcelona, Feixa Llarga s/n, 08907, L'Hospitalet de Llobregat, Catalunya, Spain.
Institut d'Investigació Biomèdica de Bellvitge, IDIBELL, 08907, L'Hospitalet de Llobregat, Catalunya, Spain.
J Assoc Res Otolaryngol. 2019 Dec;20(6):553-563. doi: 10.1007/s10162-019-00730-6. Epub 2019 Jul 11.
The tail-lift reflex and the air-righting reflex are anti-gravity reflexes in rats that depend on vestibular function. To obtain objective and quantitative measures of performance, we recorded these reflexes with slow-motion video in two experiments. In the first experiment, vestibular dysfunction was elicited by acute exposure to 0 (control), 400, 600, or 1000 mg/kg of 3,3'-iminodipropionitrile (IDPN), which causes dose-dependent hair cell degeneration. In the second, rats were exposed to sub-chronic IDPN in the drinking water for 0 (control), 4, or 8 weeks; this causes reversible or irreversible loss of vestibular function depending on exposure time. In the tail-lift test, we obtained the minimum angle defined during the lift and descent maneuver by the nose, the back of the neck, and the base of the tail. In the air-righting test, we obtained the time to right the head. We also obtained vestibular dysfunction ratings (VDRs) using a previously validated behavioral test battery. Each measure, VDR, tail-lift angle, and air-righting time demonstrated dose-dependent loss of vestibular function after acute IDPN and time-dependent loss of vestibular function after sub-chronic IDPN. All measures showed high correlations between each other, and maximal correlation coefficients were found between VDRs and tail-lift angles. In scanning electron microscopy evaluation of the vestibular sensory epithelia, the utricle and the saccule showed diverse pathological outcomes, suggesting that they have a different role in these reflexes. We conclude that these anti-gravity reflexes provide useful objective and quantitative measures of vestibular function in rats that are open to further development.
尾提升反射和空气复位反射是大鼠的抗重力反射，依赖于前庭功能。为了获得性能的客观和定量测量，我们在两个实验中使用慢动作视频记录了这些反射。在第一个实验中，急性暴露于 0（对照）、400、600 或 1000mg/kg 的 3,3'-亚氨基二丙腈（IDPN）会引起前庭功能障碍，这会导致毛细胞退化的剂量依赖性。在第二个实验中，大鼠在饮用水中暴露于亚慢性 IDPN 0（对照）、4 或 8 周；这会导致前庭功能可逆或不可逆丧失，具体取决于暴露时间。在尾提升测试中，我们获得了鼻子、颈部背面和尾巴基部在提升和下降过程中定义的最小角度。在空气复位测试中，我们获得了头部复位的时间。我们还使用先前验证的行为测试组合获得了前庭功能障碍评分（VDR）。每个测量值，VDR、尾提升角度和空气复位时间，在急性 IDPN 后都显示出前庭功能的剂量依赖性丧失，在亚慢性 IDPN 后显示出前庭功能的时间依赖性丧失。所有测量值彼此之间都显示出高度相关性，VDR 和尾提升角度之间的最大相关系数。在对前庭感觉上皮的扫描电子显微镜评估中，椭圆囊和球囊显示出不同的病理结果，表明它们在这些反射中具有不同的作用。我们得出结论，这些抗重力反射为大鼠的前庭功能提供了有用的客观和定量测量，这些测量方法可以进一步发展。
