Origin and function of short-latency inputs to the neural substrates underlying the acoustic startle reflex.
Origin and function of short-latency inputs to the neural substrates underlying the acoustic startle reflex.
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DOI：
10.3389/fnins.2014.00216
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发表时间：
2014
影响因子：
4.3
通讯作者：
López DE
中科院分区：
文献类型：
--
作者：
Gómez-Nieto R;Horta-Júnior Jde A;Castellano O;Millian-Morell L;Rubio ME;López DE
声学惊吓反射(ASR)是一种幸存的警报机制，它能迅速向生物体发出突然响亮的听觉刺激。在大鼠，初级ASR回路包括三个串联的结构：耳蜗根神经元(CRN)、脑桥尾侧网状核(PNC)的神经元以及延髓和脊髓的运动神经元。众所周知，CRN和PNC神经元都接受短潜伏期的听觉输入来调节ASR。在这里，我们使用一种结合了形态、电生理和行为技术的多学科方法来研究这些输入的解剖来源和功能作用。耳蜗顺行示踪剂注射表明，CRN胞体和树突分别根据其耳蜗基底部或顶端来源接受输入。共聚焦共定位实验表明，这些耳蜗区的输入对囊泡谷氨酸转运蛋白1(VGLUT1)呈免疫阳性反应。利用活体细胞外记录和随后的示踪剂注射，我们研究了PNC神经元在对侧、IPSI和双侧声刺激后的反应，并确定了其听觉传入的来源。结果表明，双耳PNC神经元的放电频率高于单耳，对侧声刺激表现出高于同侧声刺激的棘波放电。我们的组织学分析证实CRN是短潜伏期声音输入的主要来源，并表明耳蜗核复合体的其他区域不太可能神经支配PNC。在行为上，我们观察到单耳耳塞大鼠ASR幅度的显著降低，这与我们的电生理发现中显示的双耳总和过程相一致。我们的研究有助于更好地理解神经元机制在听觉警觉行为中的作用，并为CRNS-PNC通路介导ASR的快速神经传递和双耳总和提供了强有力的证据。
The acoustic startle reflex (ASR) is a survival mechanism of alarm, which rapidly alerts the organism to a sudden loud auditory stimulus. In rats, the primary ASR circuit encompasses three serially connected structures: cochlear root neurons (CRNs), neurons in the caudal pontine reticular nucleus (PnC), and motoneurons in the medulla and spinal cord. It is well-established that both CRNs and PnC neurons receive short-latency auditory inputs to mediate the ASR. Here, we investigated the anatomical origin and functional role of these inputs using a multidisciplinary approach that combines morphological, electrophysiological and behavioral techniques. Anterograde tracer injections into the cochlea suggest that CRNs somata and dendrites receive inputs depending, respectively, on their basal or apical cochlear origin. Confocal colocalization experiments demonstrated that these cochlear inputs are immunopositive for the vesicular glutamate transporter 1 (VGLUT1). Using extracellular recordings in vivo followed by subsequent tracer injections, we investigated the response of PnC neurons after contra-, ipsi-, and bilateral acoustic stimulation and identified the source of their auditory afferents. Our results showed that the binaural firing rate of PnC neurons was higher than the monaural, exhibiting higher spike discharges with contralateral than ipsilateral acoustic stimulations. Our histological analysis confirmed the CRNs as the principal source of short-latency acoustic inputs, and indicated that other areas of the cochlear nucleus complex are not likely to innervate PnC. Behaviorally, we observed a strong reduction of ASR amplitude in monaural earplugged rats that corresponds with the binaural summation process shown in our electrophysiological findings. Our study contributes to understand better the role of neuronal mechanisms in auditory alerting behaviors and provides strong evidence that the CRNs-PnC pathway mediates fast neurotransmission and binaural summation of the ASR.
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影响因子：
2.9
作者：
BEYERL, BD
通讯作者：
BEYERL, BD
影响因子：
2.9
作者：
DAVIS, M;SHEARD, MH
通讯作者：
SHEARD, MH
影响因子：
2.5
作者：
Doucet, JR;Ryugo, DK
通讯作者：
Ryugo, DK
DOI：
10.1037/h0027308
发表时间：
1969-01-01
期刊：
JOURNAL OF COMPARATIVE AND PHYSIOLOGICAL PSYCHOLOGY
影响因子：
--
作者：
DAVIS, M;WAGNER, AR
通讯作者：
WAGNER, AR
影响因子：
2.5
作者：
CANT, NB;GASTON, KC
通讯作者：
GASTON, KC