Analytical solution of reaction-diffusion equations for calcium wave propagation in a starburst amacrine cell
A reaction-diffusion model is presented to encapsulate calcium-induced calcium release (CICR) as a potential mechanism for somatofugal bias of dendritic calcium movement in starburst amacrine cells. Calcium dynamics involves a simple calcium extrusion (pump) and a buffering mechanism of calcium bind...
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| Format: | Article |
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Imperial College Press
2010
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| author | Poznanski, R.R. |
| author_facet | Poznanski, R.R. |
| author_sort | Poznanski, R.R. |
| collection | UM |
| description | A reaction-diffusion model is presented to encapsulate calcium-induced calcium release (CICR) as a potential mechanism for somatofugal bias of dendritic calcium movement in starburst amacrine cells. Calcium dynamics involves a simple calcium extrusion (pump) and a buffering mechanism of calcium binding proteins homogeneously distributed over the plasma membrane of the endoplasmic reticulum within starburst amacrine cells. The system of reaction-diffusion equations in the excess buffer (or low calcium concentration) approximation are reformulated as a nonlinear Volterra integral equation which is solved analytically via a regular perturbation series expansion in response to calcium feedback from a continuously and uniformly distributed calcium sources. Calculation of luminal calcium diffusion in the absence of buffering enables a wave to travel at distances of 120 mu m from the soma to distal tips of a starburst amacrine cell dendrite in 100 msec, yet in the presence of discretely distributed calcium-binding proteins it is unknown whether the propagating calcium wave-front in the somatofugal direction is further impeded by endogenous buffers. If so, this would indicate CICR to be an unlikely mechanism of retinal direction selectivity in starburst amacrine cells. |
| first_indexed | 2024-03-06T05:31:13Z |
| format | Article |
| id | um.eprints-12466 |
| institution | Universiti Malaya |
| last_indexed | 2024-03-06T05:31:13Z |
| publishDate | 2010 |
| publisher | Imperial College Press |
| record_format | dspace |
| spelling | um.eprints-124662015-01-29T02:56:54Z http://eprints.um.edu.my/12466/ Analytical solution of reaction-diffusion equations for calcium wave propagation in a starburst amacrine cell Poznanski, R.R. R Medicine A reaction-diffusion model is presented to encapsulate calcium-induced calcium release (CICR) as a potential mechanism for somatofugal bias of dendritic calcium movement in starburst amacrine cells. Calcium dynamics involves a simple calcium extrusion (pump) and a buffering mechanism of calcium binding proteins homogeneously distributed over the plasma membrane of the endoplasmic reticulum within starburst amacrine cells. The system of reaction-diffusion equations in the excess buffer (or low calcium concentration) approximation are reformulated as a nonlinear Volterra integral equation which is solved analytically via a regular perturbation series expansion in response to calcium feedback from a continuously and uniformly distributed calcium sources. Calculation of luminal calcium diffusion in the absence of buffering enables a wave to travel at distances of 120 mu m from the soma to distal tips of a starburst amacrine cell dendrite in 100 msec, yet in the presence of discretely distributed calcium-binding proteins it is unknown whether the propagating calcium wave-front in the somatofugal direction is further impeded by endogenous buffers. If so, this would indicate CICR to be an unlikely mechanism of retinal direction selectivity in starburst amacrine cells. Imperial College Press 2010 Article PeerReviewed Poznanski, R.R. (2010) Analytical solution of reaction-diffusion equations for calcium wave propagation in a starburst amacrine cell. Journal of Integrative Neuroscience, 9 (3). pp. 283-297. |
| spellingShingle | R Medicine Poznanski, R.R. Analytical solution of reaction-diffusion equations for calcium wave propagation in a starburst amacrine cell |
| title | Analytical solution of reaction-diffusion equations for calcium wave propagation in a starburst amacrine cell |
| title_full | Analytical solution of reaction-diffusion equations for calcium wave propagation in a starburst amacrine cell |
| title_fullStr | Analytical solution of reaction-diffusion equations for calcium wave propagation in a starburst amacrine cell |
| title_full_unstemmed | Analytical solution of reaction-diffusion equations for calcium wave propagation in a starburst amacrine cell |
| title_short | Analytical solution of reaction-diffusion equations for calcium wave propagation in a starburst amacrine cell |
| title_sort | analytical solution of reaction diffusion equations for calcium wave propagation in a starburst amacrine cell |
| topic | R Medicine |
| work_keys_str_mv | AT poznanskirr analyticalsolutionofreactiondiffusionequationsforcalciumwavepropagationinastarburstamacrinecell |