Research On Somato-Dendritic Bursting And Its Dynamic Properties In The Pre-B(?)tzinger Complex

Experimental studies have shown that the pre-Botzinger complex in the lateral medulla oblongata of the mammalian brain stem is a key location for the generation and regulation of respiratory rhythms,and there is a special class of neurons that spontaneously generate rhythmic firing activities that are closely related to the generation of respiratory rhythms.Studies on such firing activities may lead to better understanding of respiratory activity and related diseases.In this thesis,we use a single-neuron model of the pre-Botzinger complex with electric and magnetic currents to study the neuron’s firing activities and explore its dynamic properties.We found that the calcium activated nonspecific cation current and persistent sodium current can stimulate the neuron to generate a series of special somato-dendritic bursting(SD-Bursting),which is a mixed mode firing pattern that contain different types of cluster in the same periodic cycle.We also use dynamical methods such as fast-slow decomposition and bifurcation analysis to investigate the generation and transition mechanism of the bursting.Meanwhile,we research the impact of electrical current and conductance on firing activities of the neuron.The content of this thesis is as follows.The first chapter is an introduction,including the research background and motivation,review of the previous research,research methodology,and paper content arrangement.Chapter 2 introduces basic knowledge of the respiratory system,nervous system,and dynamic system,as well as the relevant models studied in this work;Chapter 3 studies the generating and transition of SD-Bursting in the pre-Botzinger complex,and show the impact of persistent sodium ion conductance,calcium activated nonspecific cation conductance and parameter kCAN on SD-Bursting;Chapter 4 studies the pre-Botzinger complex model,featuring externally stimulated current and magnetic current,and reveals how the externally stimulated currents of different intensities Iext,as well as the variation of parameter kCAN influence the SD-Bursting;Chapter 5 is the summary.