Motor Circuit-Specific Burst Patterns Drive Different Muscle and Behavior Patterns
Motor Circuit-Specific Burst Patterns Drive Different Muscle and Behavior Patterns
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DOI：
10.1523/jneurosci.1060-13.2013
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发表时间：
2013-07-17
影响因子：
5.3
通讯作者：
Nusbaum, Michael P.
中科院分区：
文献类型：
--
作者：
Diehl, Florian;White, Rachel S.;Nusbaum, Michael P.
在孤立的中枢神经系统中，不同的调制输入可以使一个运动网络产生多种输出模式。然而，到目前为止，很少有研究确定不同的调节输入是否也使一个定义的网络在体内驱动不同的肌肉和运动模式，就像它们在行为研究中实现这些区别一样。这种可能性不是一个预先确定的结论，因为体内存在额外的影响（例如，感觉反馈，激素调节）可以改变运动模式。此外，有节奏的神经元活动可以转化为持续的肌肉收缩，特别是在肌肉动力学缓慢的系统中，如在这里使用的螃蟹（巨蟹座）口胃系统。我们评估了两个不同版本的双相（延长，收缩）胃磨（咀嚼）的节奏，在孤立的口胃系统中触发的调制腹心神经元（VCN）和食管后连合（POC）神经元，驱动不同的肌肉和运动模式。这些节律之间的一个区别是，胃外侧（LG）延长肌运动神经元在VCN节律期间产生紧张性爆发，而其POC节律爆发被分为快速、有节奏的爆发。细胞内肌纤维记录和张力测量表明，LG神经支配的肌肉保留了不同的VCN-LG和POC-LG神经元爆发结构。此外，内窥镜视频记录在体内，在VCN触发和POC触发的咀嚼，表明侧齿的前伸运动表现出相同的，不同的前伸模式产生的LG在孤立的神经系统。因此，在分离的CNS中鉴定的运动网络的多功能性质可以在体内保留，其中它驱动不同的肌肉活动和运动模式。
In the isolated CNS, different modulatory inputs can enable one motor network to generate multiple output patterns. Thus far, however, few studies have established whether different modulatory inputs also enable a defined network to drive distinct muscle and movement patterns in vivo, much as they enable these distinctions in behavioral studies. This possibility is not a foregone conclusion, because additional influences present in vivo (e.g., sensory feedback, hormonal modulation) could alter the motor patterns. Additionally, rhythmic neuronal activity can be transformed into sustained muscle contractions, particularly in systems with slow muscle dynamics, as in the crab (Cancer borealis) stomatogastric system used here. We assessed whether two different versions of the biphasic (protraction, retraction) gastric mill (chewing) rhythm, triggered in the isolated stomatogastric system by the modulatory ventral cardiac neurons (VCNs) and postoesophageal commissure (POC) neurons, drive different muscle and movement patterns. One distinction between these rhythms is that the lateral gastric (LG) protractor motor neuron generates tonic bursts during the VCN rhythm, whereas its POC-rhythm bursts are divided into fast, rhythmic burstlets. Intracellular muscle fiber recordings and tension measurements show that the LG-innervated muscles retain the distinct VCN-LG and POC-LG neuron burst structures. Moreover, endoscope video recordings in vivo, during VCN-triggered and POC-triggered chewing, show that the lateral teeth protraction movements exhibit the same, distinct protraction patterns generated by LG in the isolated nervous system. Thus, the multifunctional nature of an identified motor network in the isolated CNS can be preserved in vivo, where it drives different muscle activity and movement patterns.