Alpha-9 nicotinic acetylcholine receptors mediate hypothermic responses elicited by provocative motion in mice
Alpha-9 nicotinic acetylcholine receptors mediate hypothermic responses elicited by provocative motion in mice
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DOI：
10.1016/j.physbeh.2017.03.012
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发表时间：
2017-05-15
影响因子：
2.9
通讯作者：
Nalivaiko, Eugene
中科院分区：
文献类型：
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作者：
Tu, Longlong;Poppi, Lauren;Nalivaiko, Eugene
人类晕车时会出现体温过低反应，而大鼠的刺激性运动可能会引发体温过低反应。我们的目的是确定传出胆碱能前庭神经支配的这些反应中的潜在作用。为此，我们使用缺乏主要在前庭毛细胞中表达的α9胆碱受体亚基的敲除（KO）小鼠和作为野生型（WT）对照的CBA品系。在WT小鼠中，水平圆周运动（1赫兹，4厘米半径，20分钟）导致核心体温和头部表面温度快速急剧下降，并伴有尾部温度短暂升高；这些反应在 MO 小鼠中显着减弱；变化为（WT 与 MO）：核心体温 -52 +/- 0.3 与 -2.9 +/- 03 摄氏度；头部皮肤温度 -33 +/- 0.2 与 -1.7 +/- 0.2 摄氏度；尾部皮肤温度 + 3.9 +/- 1.1 与 + 1.1 +/- 1.2 摄氏度。身体和头部表面冷却的时间过程密切相关。 MO 小鼠还需要 25% 的时间才能完成平衡测试。我们的结论是：i）胆碱能传出前庭系统的完整性对于小鼠运动引起的体温过低的充分表达至关重要，并且该系统的作用可能是促进性的； ii) 系统参与平衡控制，但参与程度并不重大； iii) 在小鼠中，运动引起的身体冷却是通过血管舒张的尾部脉管系统的热流增加以及（可能）产热作用的减少来介导的。我们的结果支持这样的观点，即体温过低是动物恶心样状态的生物学相关性。 (C) 2017 Elsevier Inc. 保留所有权利。
Hypothermic responses accompany motion sickness in humans and can be elicited by provocative motion in rats. We aimed to determine the potential role in these responses of the efferent cholinergic vestibular innervation. To this end, we used knockout (KO) mice lacking alpha 9 cholinoreceptor subunit predominantly expressed in the vestibular hair cells and CBA strain as a wild-type (WT) control. In WT mice, circular horizontal motion (1 Hz, 4 cm radius, 20 min) caused rapid and dramatic falls in core body temperature and surface head temperature associated with a transient rise in the tail temperature; these responses were substantially attenuated in MO mice; changes were (WT vs. MO): for the core body temperature -52 +/- 0.3 vs. -2.9 +/- 03 degrees C; for the head skin temperature -33 +/- 0.2 vs. -1.7 +/- 0.2 degrees C; for the tail skin temperature + 3.9 +/- 1.1 vs + 1.1 +/- 1.2 degrees C. There was a close correlation in the time course of cooling the body and the surface of the head. MO mice also required 25% more time to complete a balance test. We conclude: i) that the integrity of cholinergic efferent vestibular system is essential for the full expression of motion-induced hypothermia in mice, and that the role of this system is likely facilitatory; ii) that the system is involvement in control of balance, but the involvement is not major; iii) that in mice, motion-induced body cooling is mediated via increased heat flow through vasodilated tail vasculature and (likely) via reduced thermogenesis. Our results support the idea that hypothermia is a biological correlate of a nausea-like state in animals. (C) 2017 Elsevier Inc. All rights reserved.