Author: Harley Ewing
Ewing, Harley, 2020 Modelling action potential firing rate of mouse bladder afferent nerves in an inflated bladder using finite element analysis and Hodgkin-Huxley models, Flinders University, College of Science and Engineering
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This study modelled the action potential firing rate of mouse bladder afferent nerves for an inflated bladder using a finite element analysis and a Hodgkin-Huxley model. Pressure curve data was captured for in vitro mouse bladders using a multistage volumetric inflation. A 3D model replicating mouse bladder dimensions was constructed for the finite element model. Material properties and boundary conditions for the finite element model were assigned to emulate the in vitro bladder properties. The finite element model was performed in two stages, with the first stage capturing the displacement coordinates for the final volume, and the second stage capturing the viscoelastic stress response and staged volumetric inflation. Stress and displacement data were combined to recreate the in vitro pressure curves for finite element analysis model validation. A stimulus in the form of stress values from multiple nodes on the finite element model was applied to a modified Hodgkin-Huxley model. The Hodgkin-Huxley model generates a series of action potentials from which the firing rate is calculated. The stimulus stress values were input to the Hodgkin-Huxley model using both a linear relation and an exponential relation. Single nodes were examined showing that firing rate changes as a function of position for models where the stiffness changes as a function of position. Multiple node outputs were combined to simulate a receptor field, showing that firing rate increases as node count increases. Model validation was performed against existing firing rate data for a pressure volume curve. The exponentially modelled input was found to be a better fit for firing rate data validation.
Keywords: action potential, firing rate, mouse bladder afferent nerves, mouse bladder, afferent nerves, inflated bladder, finite element analysis, fea, fem, hodgkin-huxley, h-h, stress response, viscoelastic, pressure volume curve
Subject: Engineering thesis
Thesis type: Masters
Completed: 2020
School: College of Science and Engineering
Supervisor: Professor Mark Taylor