Neural control of respiration in lampreys

呼吸是一种重要的运动行为，从出生时就开始了，并一直维持到一生。呼吸的病理变化可能会产生可怕的后果，因此了解产生呼吸的神经机制是至关重要的。要做到这一点，必须识别整个网络的突触连通性以及组成生成器神经元的膜特性。哺乳动物中枢神经系统(CNS)的复杂性使这项任务变得困难，我们相信较简单的七鳃鳗中枢神经系统可以帮助提供详细的了解。七鳃鳗在体外分离其中枢神经系统后，产生呼吸的神经回路保持活跃，并继续产生与在完整动物中观察到的非常相似的呼吸输出。我们建议在系统(突触连接)和细胞(神经元的固有特性)两个水平上描述七鳃鳗中枢神经回路的特征。突触和固有属性在呼吸中的相对贡献也将被确立。最后，我们将研究在孤立的中枢神经系统中其他马达电路对呼吸的调制。运动的开始伴随着呼吸驱动的增加，我们实验室之前的工作表明，这种变化是在中枢神经系统预先编程的。我们建议确定负责这些变化的神经回路。我们相信，在这一低等脊椎动物中枢神经系统中获得的信息将有助于为包括人类在内的高等脊椎动物中负责呼吸的神经组织提供可检验的假说。

Respiration is a vital motor behaviour that begins at birth and is maintained throughout life. Pathological changes in breathing can have dire consequences and it is thus crucial to understand the neural mechanisms generating respiration. To do this, both the synaptic connectivity of the entire network as well as the membrane properties of the comprising generator neurons must be identified. The complexity of the mammalian Central Nervous System (CNS) renders this task difficult and we believe that the simpler CNS of lampreys could help provide a detailed understanding. In lampreys, the neural circuitry generating respiration stays active after isolation in vitro of their CNS, and continues to generate respiratory output very similar to that observed in intact animals. We propose to characterize the neural circuitry both at the system (synaptic connectivity) and cellular (intrinsic properties of neurons) levels in the CNS of lampreys. The relative contribution of synaptic and intrinsic properties in respiration will also be established. Finally, we will examine the modulation of respiration by other motor circuits in the isolated CNS. The onset of movements is accompanied by increases in the respiratory drive and previous work from our lab has revealed that the changes are pre-programmed in the CNS. We propose to identify the neural circuitry responsible for these changes. We believe that the information gained in this lower vertebrate CNS will be useful to provide testable hypotheses on the neural organization responsible for respiration in higher vertebrates, including humans.