Responses of neurons in the rostral ventrolateral medulla to whole body rotations: comparisons in decerebrate and conscious cats
Responses of neurons in the rostral ventrolateral medulla to whole body rotations: comparisons in decerebrate and conscious cats
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DOI：
10.1152/japplphysiol.00180.2011
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发表时间：
2011-06-01
影响因子：
3.3
通讯作者：
Yates, B. J.
中科院分区：
文献类型：
--
作者：
DeStefino, V. J.;Reighard, D. A.;Yates, B. J.
DeStefino VJ，Reighard DA，Sugiyama Y，Suzuki T，Cotter LA，Larson MG，Gandhi NJ，Barman SM，Yates BJ.延髓头端腹外侧区神经元对全身旋转的反应：去大脑和清醒猫的比较。J Appl Physiol 110：1699-1707，2011.首次发表于2011年4月14日; doi：10.1152/japplphysiol.00180.2011。脑干神经元调节交感神经流出和血流的前庭刺激的反应已被广泛研究去大脑的准备，但没有在清醒的动物。在本研究中，我们比较了在延髓头端腹外侧区（RVLM），参与血压调节的脑干的主要区域的神经元的反应，意识和去脑猫的全身旋转。在两种制剂中，RVLM神经元表现出相似水平的自发活动（中位数相似于17个尖峰/秒）。记录在去脑猫的RVLM神经元的约一半的发射调制旋转，这些细胞被激活的垂直倾斜在不同的方向，与响应特性表明，他们的arthine输入起源于耳石器官。超过三分之一的RVLM神经元在去大脑动物的活动被改变的压力感受器的刺激; RVLM单位有和没有压力感受器信号有类似的反应旋转。相比之下，在有意识的猫中，只有6%的RVLM神经元表现出与心脏相关的活动，只有1%的细胞的放电受到旋转的调节。这些数据表明，脑干电路介导前庭交感神经反射是高度敏感的空间中的身体位置的变化，但前庭刺激的神经元的反应在通路中被抑制的更高的大脑中心在有意识的动物。研究结果还提出了一种可能性，即对各种输入（包括来自内耳的输入）的自主反应可以根据行为背景进行门控，并在不必要时减弱。
DeStefino VJ, Reighard DA, Sugiyama Y, Suzuki T, Cotter LA, Larson MG, Gandhi NJ, Barman SM, Yates BJ. Responses of neurons in the rostral ventrolateral medulla to whole body rotations: comparisons in decerebrate and conscious cats. J Appl Physiol 110: 1699-1707, 2011. First published April 14, 2011; doi:10.1152/japplphysiol.00180.2011.-The responses to vestibular stimulation of brain stem neurons that regulate sympathetic outflow and blood flow have been studied extensively in decerebrate preparations, but not in conscious animals. In the present study, we compared the responses of neurons in the rostral ventrolateral medulla (RVLM), a principal region of the brain stem involved in the regulation of blood pressure, to whole body rotations of conscious and decerebrate cats. In both preparations, RVLM neurons exhibited similar levels of spontaneous activity (median of similar to 17 spikes/s). The firing of about half of the RVLM neurons recorded in decerebrate cats was modulated by rotations; these cells were activated by vertical tilts in a variety of directions, with response characteristics suggesting that their labyrinthine inputs originated in otolith organs. The activity of over one-third of RVLM neurons in decerebrate animals was altered by stimulation of baroreceptors; RVLM units with and without baroreceptor signals had similar responses to rotations. In contrast, only 6% of RVLM neurons studied in conscious cats exhibited cardiac-related activity, and the firing of just 1% of the cells was modulated by rotations. These data suggest that the brain stem circuitry mediating vestibulosympathetic reflexes is highly sensitive to changes in body position in space but that the responses to vestibular stimuli of neurons in the pathway are suppressed by higher brain centers in conscious animals. The findings also raise the possibility that autonomic responses to a variety of inputs, including those from the inner ear, could be gated according to behavioral context and attenuated when they are not necessary.