Modelling respiratory rhythmogenesis: focus on phase switching mechanisms.
Modelling respiratory rhythmogenesis: focus on phase switching mechanisms.
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呼吸节律发生建模：关注相位切换机制。
DOI：
10.1007/0-387-27023-x_29
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发表时间：
2004
影响因子：
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通讯作者：
Haji,Akira
中科院分区：
文献类型：
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作者：
Rybak,IlyaA;Shevtsova,NataliaA;Paton,JulianFR;Pierrefiche,Olivier;St-John,WalterM;Haji,Akira
已经确定，哺乳动物的正常呼吸模式（“呼吸正常”）产生于下脑干1，2，并可能涉及几个延髓和脑桥区域。尽管一些研究人员认为，髓质内的一个较小区域（例如，前BötC复合体（pre-BötC）可能足以产生呼吸节律3 -5，正常呼吸节律（以及呼吸暂停呼吸）从未在不含脑桥的简化延髓标本中重现。与此同时，与呼吸模式的发生、形成和控制相关的特定脑桥-延髓相互作用迄今尚未得到很好的表征。在这里，我们提出了一个初步的脑桥延髓呼吸网络的计算模型，被认为是未来的互动建模实验研究的基础。该模型是使用一系列假设开发的。具体地说，我们已经提出，在正常条件下，在体内，正常呼吸节律是由脑桥延髓网络。因此，虽然前BötC是这个网络的必要组成部分，在这一地区的内在振荡被抑制在正常呼吸的脑桥延髓的相互作用。然而，这些内源性振荡可以在某些特定条件下释放，例如，在体外，由于缺乏脑桥，或在体内缺氧6。我们还假设呼吸网络的髓部分包含执行呼吸相位转换的特殊神经回路。此外，这些回路也是来自脑桥和主要传入神经的肺反馈和输入的目标，其使用相同的延髓开关回路来调节相变的时间并调节呼吸运动模式7。
It has been established that the normal respiratory pattern (“eupnoea”) in mammals is generated in the lower brainstem1,2 and may involve several medullary and pontine regions. Although some researchers suggest that a smaller region within the medulla (e.g., the pre-Bötzinger Complex (pre-BötC) may be sufficient for the respiratory rhythm generation3–5, the eupnoeic respiratory rhythm (as well as apneustic breathing) has never been reproduced in reduced medullary preparations without the pons. At the same time, the specific ponto-medullary interactions related to genesis, shaping and control of the respiratory pattern have not been well characterized so far. Here we present a preliminary computational model of the ponto-medullary respiratory network that is considered a basis for the future interactive modeling-experimental studies. The model has been developed using a series of assumptions. Specifically, we have suggested that, under normal conditionsin vivo, the eupnoeic respiratory rhythm is generated by a ponto-medullary network. Hence, although the pre-BötC is a necessary part of this network, the intrinsic oscillations in this region are suppressed during eupnoea by ponto-medullary interactions. These endogenous oscillations, however, may be released under some specific conditions, e.g.,in vitro, because of the lack of the pons, or during hypoxiain vivo6. We have also assumed that the medullary part of the respiratory network contains special neural circuits performing the respiratory phase switching. Moreover, these circuits are also targets for pulmonary feedback and inputs from the pons and major afferent nerves, which use the same medullary switching circuits to regulate the timing of phase transitions and modulate the respiratory motor pattern7.