The Botzinger complex and its role in respiratory rhythm generation

延髓呼吸中枢涉及多种呼吸神经元，产生呼吸的自动节律性，并产生与呼吸相关的肌肉的时空有组织的收缩。电生理和神经解剖学研究主要使用猫和大鼠，极大地增加了我们对整个呼吸系统及其网络机制的了解。目前，延髓腹外侧区的一个有限区域，横跨称为Botzinger复合体和前Botzinger复合体的区域，是我们关注的焦点。在这个区域，已经发现了许多具有特殊放电模式和特殊形态特征的兴奋性和抑制性神经元。这些神经元形成的网络涉及1)吸气和呼气神经元之间的抑制性连接，2)吸气神经元之间的兴奋性连接，3)呼气神经元之间的抑制性连接，以及4)吸气neu…之间的抑制性连接更多的罗恩斯。这些突触连接中的一些对于呼吸节律的产生是必不可少的，另一些对于形成有模式的呼吸输出是必不可少的。我们已经证明，Botzinger复合体的增强型和减速型呼气神经元都是呼吸节律的关键抑制神经元，它们使用甘氨酸作为抑制性递质。臂旁核周围的桥脑区，包括Kolliker-Fuse核，与呼吸控制密切相关，被称为脑桥呼吸群。我们分析了脑桥呼吸神经元的放电模式和轴突投射。识别出六种类型的放电模式。被检查的大多数呼吸神经元被延髓的电刺激反向激活。它们从腹侧呼吸群周围的延髓腹外侧部和Botzinger复合体以及延髓背内侧被激活，提示桥脑呼吸神经元与延髓呼吸神经元，包括Botzinger神经元有密切联系。较少

The medullary respiratory center involving a variety of respiratory neurons generates the automatic rhythmicity of respiration and produces the spatio-temporally organized contraction of respiration-related muscles. Electrophysiological and neuroanatomical studies using largely cats and rats, have greatly increased our knowledge about the overall respiratory system and its network mechanisms. Currently, a limited region of the ventrolateral medulla, which spans the areas called the Botzinger complex and the pre-Botzinger complex, is the focus of our attention. In this region, a number of excitatory and inhibitory neurons with specific firing patterns and characteristic morphological features have been identified. These neurons form the networks that involve 1) inhibitory connections between inspiratory and expiratory neurons, 2) excitatory connections between inspiratory neurons, 3) inhibitory connections between expiratory neurons, and 4) inhibitory connections between inspiratory neu … More rons. Some of these synaptic connections are essential for the generation of respiratory rhythm, and some for the formation of patterned respiratory outputs. We have shown that both augmenting and decrementing expiratory neurons of the Botzinger complex are key inhibitory neurons for the respiratory rhythm and that they use glycine as their inhibitory transmitter. The pontine area around the parabrachial nucleus including the Kolliker-Fuse nucleus is deeply involved in respiratory control and called the pontine respiratory group. we analyzed the firing patterns and the axonal projections of pontine respiratory neurons. Six types of firing patterns were identified. The majority of the respiratory neurons examined were antidromically activated by electrical stimulation of the medulla. They were activated from the ventrolateral medulla around the ventral respiratory group and the Botzinger complex and from the dorsomedial medulla, suggesting that the pontine respiratory neurons are closely linked with the medullary respiratory neurons including- the Botzinger neurons. Less