Spontaneous Voltage Oscillations and Response Dynamics of a Hodgkin-Huxley Type Model of Sensory Hair Cells
We employ a Hodgkin-Huxley-type model of basolateral ionic currents in bullfrog saccular hair cells for studying the genesis of spontaneous voltage oscillations and their role in shaping the response of the hair cell to external mechanical stimuli. Consistent with recent experimental reports, we find that the spontaneous dynamics of the model can be categorized using conductance parameters of calciumactivated potassium, inward rectifier potassium, and mechano-electrical transduction (MET) ionic currents. The model is demonstrated for exhibiting a broad spectrumof autonomous rhythmic activity, including periodic and quasi-periodic oscillations with two independent frequencies as well as various regular and chaotic bursting patterns. Complex patterns of spontaneous oscillations in the model emerge at small values of the conductance of Ca2+-activated potassium currents. These patterns are significantly affected by thermal fluctuations of the MET current. We show that selfsustained regular voltage oscillations lead to enhanced and sharply tuned sensitivity of the hair cell to weak mechanical periodic stimuli. While regimes of chaotic oscillations are argued to result in poor tuning to sinusoidal driving, chaotically oscillating cells do provide a high sensitivity to low-frequency variations of external stimuli.
Neiman et al.: Spontaneous voltage oscillations and response dynamics of a Hodgkin-Huxley type model of sensory hair cells. Journal of Mathematical Neuroscience (2011) 1:11. doi: 10.1186/2190-8567-1-11
Creative Commons License
This work is licensed under a Creative Commons Attribution 3.0 License.
This article was originally published in the Journal of Mathematical Neuroscience. It is posted here with the permission of the author.
Copyright © 2011 Neiman et al; licensee Springer. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.