Anatomic patterning in the expression of vestibulosympathetic reflexes
Anatomic patterning in the expression of vestibulosympathetic reflexes
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DOI：
10.1152/ajpregu.2000.279.1.r109
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发表时间：
2000-07-01
影响因子：
2.8
通讯作者：
McAllen, RM
中科院分区：
文献类型：
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作者：
Kerman, IA;Yates, BJ;McAllen, RM
为了研究前庭交感神经反射(VSR)的表达与神经的解剖位置有关的可能性，而不是与其靶器官相关，我们比较了位于三个不同的吻尾水平的同一类型节后纤维[肌肉血管收缩(MVC)]的VSR记录：后肢、前肢和面部。实验在氯醛糖麻醉的猫身上进行，前庭传入受到电刺激。通过对少纤维记录的棘波形状分析，提取单个MVC单位活动，并通过自相关确认单位区分。刺激后时间直方图分析显示，大约一半的神经元最初被前庭刺激抑制(类型1反应)，而其他MVC纤维最初被强烈兴奋(类型2反应)。同一神经束内有1、2型反应的MVC单位。气压敏感度在两组中相同，但表现为1型反应的纤维比表现为2型反应的纤维更快(0.29+/-0.04对0.20+/-0.02赫兹)。具有1型反应的神经纤维在后肢最常见(21/29个单位)，面部最少(2/11个单位)，相对比例差异有统计学意义(P<；0.05，x(2)检验)。这些结果支持了VSR是解剖学模式的假设。
To investigate the possibility that expression of vestibulosympathetic reflexes (VSR) is related to a nerve's anatomic location rather than its target organ, we compared VSR recorded from the same type of postganglionic fiber [muscle vasoconstrictor (MVC)] located at three different rostrocaudal levels: hindlimb, forelimb, and face. Experiments were performed on chloralose-anesthetized cats, and vestibular afferents were stimulated electrically. Single MVC unit activity was extracted by spike shape analysis of few-fiber recordings, and unit discrimination was confirmed by autocorrelation. Poststimulus time histogram analysis revealed that about half of the neurons were initially inhibited by vestibular stimulation (type 1 response), whereas the other MVC fibers were initially strongly excited (type 2 response). MVC units with types 1 and 2 responses were present in the same nerve fascicle. Barosensitivity was equivalent in the two groups, but fibers showing type 1 responses fired significantly faster than those giving type 2 responses (0.29 +/- 0.04 vs. 0.20 +/- 0.02 Hz). Nerve fibers with type 1 responses were most common in the hindlimb (21 of 29 units) and least common in the face (2 of 11 units), the difference in relative proportion being significant (P < 0.05, chi(2) test). These results support the hypothesis that VSR are anatomically patterned.