Abe Yasunori, Kato Chiho, Uchima Koecklin Karin Harumi, Okihara Hidemasa, Ishida Takayoshi, Fujita Koichi, Yabushita Tadachika, Kokai Satoshi, Ono Takashi
Orthodontic Science, Department of Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
Orthodontic Science, Department of Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan.
J Appl Physiol (1985). 2017 Jun 1;122(6):1494-1503. doi: 10.1152/japplphysiol.01130.2016. Epub 2017 Mar 23.
Postnatal growth is influenced by genetic and environmental factors. Nasal obstruction during growth alters the electromyographic activity of orofacial muscles. The facial primary motor area represents muscles of the tongue and jaw, which are essential in regulating orofacial motor functions, including chewing and jaw opening. This study aimed to evaluate the effect of chronic unilateral nasal obstruction during growth on the motor representations within the face primary motor cortex (M1). Seventy-two 6-day-old male Wistar rats were randomly divided into control ( = 36) and experimental ( = 36) groups. Rats in the experimental group underwent unilateral nasal obstruction after cauterization of the external nostril at 8 days of age. Intracortical microstimulation (ICMS) mapping was performed when the rats were 5, 7, 9, and 11 wk old in control and experimental groups ( = 9 per group per time point). Repeated-measures multivariate ANOVA was used for intergroup and intragroup statistical comparisons. In the control and experimental groups, the total number of positive ICMS sites for the genioglossus and anterior digastric muscles was significantly higher at 5, 7, and 9 wk, but there was no significant difference between 9 and 11 wk of age. Moreover, the total number of positive ICMS sites was significantly smaller in the experimental group than in the control at each age. It is possible that nasal obstruction induced the initial changes in orofacial motor behavior in response to the altered respiratory pattern, which eventually contributed to face-M1 neuroplasticity. Unilateral nasal obstruction in rats during growth periods induced changes in arterial oxygen saturation (SpO) and altered development of the motor representation within the face primary cortex. Unilateral nasal obstruction occurring during growth periods may greatly affect not only respiratory function but also craniofacial function in rats. Nasal obstruction should be treated as soon as possible to avoid adverse effects on normal growth, development, and physiological functions.
出生后的生长受遗传和环境因素影响。生长期间的鼻塞会改变口面部肌肉的肌电活动。面部初级运动区代表舌和颌部肌肉，这些肌肉在调节口面部运动功能（包括咀嚼和张口）中至关重要。本研究旨在评估生长期间慢性单侧鼻塞对面部初级运动皮层（M1）内运动表征的影响。72只6日龄雄性Wistar大鼠被随机分为对照组（n = 36）和实验组（n = 36）。实验组大鼠在8日龄时对外侧鼻孔进行烧灼后接受单侧鼻塞处理。在对照组和实验组大鼠5、7、9和11周龄时进行皮层内微刺激（ICMS）图谱绘制（每组每个时间点n = 9）。采用重复测量多因素方差分析进行组间和组内的统计学比较。在对照组和实验组中，颏舌肌和二腹肌前腹的阳性ICMS位点总数在5、7和9周时显著更高，但在9周和11周龄之间无显著差异。此外，在每个年龄，实验组的阳性ICMS位点总数均显著少于对照组。鼻塞可能因呼吸模式改变诱发了口面部运动行为的初始变化，最终导致了面部M1区的神经可塑性。生长期间大鼠单侧鼻塞会导致动脉血氧饱和度（SpO）变化，并改变面部初级皮层内运动表征的发育。生长期间发生的单侧鼻塞可能不仅会极大影响大鼠的呼吸功能，还会影响其颅面功能。应尽早治疗鼻塞，以避免对正常生长、发育和生理功能产生不利影响。
