Multimodal medullary neurons and correlational linkages of the respiratory network.
Multimodal medullary neurons and correlational linkages of the respiratory network.
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多模式髓质神经元和呼吸网络的相关联动。
DOI：
10.1152/jn.1999.82.1.188
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发表时间：
1999
期刊：
影响因子：
--
通讯作者：
Lindsey,BG
中科院分区：
文献类型：
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作者：
Li,Z;Morris,KF;Baekey,DM;Shannon,R;Lindsey,BG
这项研究解决了这样一个假设，即多个感觉系统，每一个都能够反射性地改变呼吸，共同影响脑干呼吸网络的神经元。在33只Dial-氨基甲酸乙酯麻醉或去大脑迷走神经切断的成年猫中，依次刺激颈动脉化学感受器、压力感受器和足垫伤害感受器。用微电极阵列监测头、尾侧腹侧呼吸组（VRG）、孤束核（NTS）和n。暗缝记录传出膈神经活动。使用周期触发直方图分析889个神经元的棘波序列，并测试周期调制的放电率。刺激方案的反应进行了评估，周刺激时间和累积和直方图。交叉相关分析被用来测试穗列车之间的非随机时间关系。棘波触发平均传出膈神经活动和逆向刺激方法提供的证据延髓神经元与膈运动神经元的功能协会。计算了6，471对神经元的尖峰串交叉相关图。425对被检测到显著的相关图特征，包括189个主中心峰或谷，156个偏移峰或谷，和80对具有多个峰和谷。结果提供的证据表明，相关的髓质组件包括神经元重叠成员的群体响应不同的感觉方式。这些数据提示并支持了关于调节呼吸运动模式的合作关系的几个假设：1）对单一测试模态有反应的神经元促进或限制多模态靶神经元的放电率的变化; 2）多模态神经元有助于对单一测试模态有反应的神经元的放电率的变化; 3）多模态神经元可能在一种模态刺激期间促进反应并“限制”多模态靶神经元的放电率。在另一感觉模态的刺激期间放电速率的变化。4）尾侧VRG吸气神经元具有抑制性连接，其提供吸气驱动和相持续时间的负反馈调节。
This study addresses the hypothesis that multiple sensory systems, each capable of reflexly altering breathing, jointly influence neurons of the brain stem respiratory network. Carotid chemoreceptors, baroreceptors, and foot pad nociceptors were stimulated sequentially in 33 Dial-urethan–anesthetized or decerebrate vagotomized adult cats. Neuronal impulses were monitored with microelectrode arrays in the rostral and caudal ventral respiratory group (VRG), nucleus tractus solitarius (NTS), and n. raphe obscurus. Efferent phrenic nerve activity was recorded. Spike trains of 889 neurons were analyzed with cycle-triggered histograms and tested for respiratory-modulated firing rates. Responses to stimulus protocols were assessed with peristimulus time and cumulative sum histograms. Cross-correlation analysis was used to test for nonrandom temporal relationships between spike trains. Spike-triggered averages of efferent phrenic activity and antidromic stimulation methods provided evidence for functional associations of bulbar neurons with phrenic motoneurons. Spike train cross-correlograms were calculated for 6,471 pairs of neurons. Significant correlogram features were detected for 425 pairs, including 189 primary central peaks or troughs, 156 offset peaks or troughs, and 80 pairs with multiple peaks and troughs. The results provide evidence that correlational medullary assemblies include neurons with overlapping memberships in groups responsive to different sets of sensory modalities. The data suggest and support several hypotheses concerning cooperative relationships that modulate the respiratory motor pattern.1) Neurons responsive to a single tested modality promote or limit changes in firing rate of multimodal target neurons.2) Multimodal neurons contribute to changes in firing rate of neurons responsive to a single tested modality.3) Multimodal neurons may promote responses during stimulation of one modality and “limit” changes in firing rates during stimulation of another sensory modality.4) Caudal VRG inspiratory neurons have inhibitory connections that provide negative feedback regulation of inspiratory drive and phase duration.