Modeling of cellular and network neural mechanisms for respiratory pattern generation

The objectives of the research were to develop a computational model of the central generator of the respiratory pattern (CGRP) and to explore the roles of intrinsic biophysical properties of respiratory neurons in interactions with network properties in CGRP performance. The models of specific single respiratory neurons were developed in the Hodgkin-Huxley style and include sodium and a series of potassium and calcium channels. The different models produced the specific firing patterns of respiratory neurons recorded experimentally (i.e. adapting and ramping bursts). The CGRP model included: a network of respiratory neurons with different intrinsic properties, peripheral feedback from pulmonary stretch receptors and inputs from other nerves. The model demonstrated both a stable respiratory rhythm and the specific patterns of respiratory neuronal discharges recorded experimentally. Our model shows how calcium and calcium dependent channels in different respiratory neurons, in interaction with properties of the respiratory network, provide: (i) shaping of the specific neuronal patterns; (ii) respiratory rhythm generation, and (iii) control of the respiratory phase snitching.