外加电流和磁流下前包钦格复合体神经元中混合簇放电的动力学分析

Dynamical Analysis of Mixed Burster in the Pre-Botzinger Complex Under the Magnetic Flow and Current

新生哺乳动物呼吸节律的产生与pre-Botzinger复合体中神经元的节律性放电密切相关.放电行为是神经系统中一种复杂的非线性现象,表现为多种模式.混合簇放电是实验观察到的一类放电模式,其产生涉及复杂的动力学机制.磁流和电流的引入对神经元的放电模式具有重要的调节作用.我们分别探索了磁流和电流对单个pre-Botzinger复合体神经元内混合簇放电模式的影响.通过快慢分解和双参数分岔分析,研究了磁流和电流对混合簇放电的产生及转迁的动力学机制.结果表明,磁流和刺激电流都能引起混合簇个数的增减性的多次变化,不同于其它簇放电在磁流和刺激电流的作用下引起混合簇个数的单调增加或减少的现象,该结果显示了节律变化现象的多样性.本研究结果有助于揭示和解释呼吸节律中复杂节律模式的动力学机制.

The generation of respiratory rhythms in newborn mammals is critically involved in the rhythmic firing of neurons in the pre-Botzinger complex.Rhythmic activity is a complex nonlinear phenomenon in the nervous system,which manifests as diverse patterns.One special somato-dendritic bursting observed experimentally is the mixed burster.It consists of two or more different types of bursters in each period,involving extremely complex dynamic mechanisms.The introduction of magnetic flow and direct current stimulation plays an important role in regulating the firing pattern of neurons.We explore separately the effects of magnetic flow and current on the rhythmic patterns of mixed bursting within individual pre-Botzinger complex neurons.By fast and slow decomposition and two-parameter bifurcation analysis,the dynamic mechanism of generation and transition of mixed bursting by magnetic flow and direct current is investigated.The results show that both the magnetic flow and direct current can cause multiple changes in the increase and decrease of the number of somatic bursts in the mixed bursting.Different from other phenomena in which the number of mixed bursting is monotonically increased or decreased,the results show the diversity phenomenon of rhythm activity.The results of the present study may help to reveal and explain the dynamic mechanism of the complex mixed pattern of respiratory rhythm.