Paton J F, Ramirez J M, Richter D W
Physiologisches Institut, Universität Göttingen, FRG.
Neurosci Lett. 1994 Mar 28;170(1):167-70. doi: 10.1016/0304-3940(94)90265-8.
To study the ontogenesis of central respiratory rhythm generation, a novel brainstem slice preparation was developed that generates respiratory rhythmic activity spontaneously in mice and rats at all post-natal ages. The slice was made by tilting the brainstem to include both the ventrolateral and dorsomedial medulla. This 'tilted-sagittal' slice contained the nucleus ambiguus, the hypoglossal motor nucleus (XII) and the nucleus of the solitary tract which were preserved intact throughout their rostro-caudal extent. Using this rhythmic preparation it has been possible for the first time to directly compare the significance of glycinergic mechanisms for respiratory rhythmogenesis between newborns and mature rodents in vitro. Our findings demonstrate that during the first two weeks of life there are profound changes in both the motor pattern of rhythmic XII neurons and sensitivity of the respiratory rhythm to strychnine blockade of glycine receptors. Thus, developmental changes in strychnine-sensitive receptors are vital for the maturation of the respiratory network and it is suggested that any disturbance in their development may be lethal.
为了研究中枢呼吸节律产生的个体发生，开发了一种新型脑干切片制备方法，该方法能使小鼠和大鼠在所有出生后的年龄段自发产生呼吸节律活动。切片是通过倾斜脑干制成的，以包括腹外侧和背内侧延髓。这种“倾斜矢状”切片包含疑核、舌下运动核（XII）和孤束核，这些核在其整个 rostro - 尾侧范围内都保持完整。利用这种有节律的制备方法，首次有可能在体外直接比较新生和成熟啮齿动物中甘氨酸能机制对呼吸节律发生的重要性。我们的研究结果表明，在出生后的前两周内，节律性 XII 神经元的运动模式以及呼吸节律对士的宁阻断甘氨酸受体的敏感性都发生了深刻变化。因此，士的宁敏感受体的发育变化对于呼吸网络的成熟至关重要，并且有人提出其发育过程中的任何干扰都可能是致命的。
