Modeling of basolateral ATP release induced by hypotonic treatment in A6 cells.
ATP is released from the basolateral membrane of A6 epithelia in response to hypotonic treatment. This study addresses the problem of ATP diffusion through the permeable supports used to culture the cells. A theoretical analysis of a recently introduced experimental protocol is presented and a model of ATP diffusion through the compartments of the measuring system is proposed. The model provides the ATP profiles near the cell layer and in the measurement chamber. Comparison of results from computer simulations and experimental data showed that the permeable support introduces a marked delay for ATP diffusion, supporting the correlation of apparently time-separated events: the mobilization of Ca(2+) from internal stores and release of ATP from the cell. The model is consistent with experimental data obtained with the luciferin-luciferase pulse protocol and provides an indirect proof of related processes like the closure and opening of the lateral interspace that occur after imposing the hyposmotic shock. The influence of the pore structure of the permeable support in modulating the measured release rates revealed by computer simulation is experimentally validated for two types of Anopore filters.
Gheorghiu
Mihaela
M
International Centre of Biodynamics, Calea Plevnei 46-48, 010233, Bucharest 1, Romania. mgheorghiu@biodyn.ro
Van Driessche
Willy
W
D000255:Adenosine Triphosphate / Q000378:metabolism*; D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002460:Cell Line; D002462:Cell Membrane / Q000187:drug effects / Q000502:physiology*; D002463:Cell Membrane Permeability / Q000187:drug effects / Q000502:physiology*; D003198:Computer Simulation; D004058:Diffusion / Q000187:drug effects; D004847:Epithelial Cells / Q000187:drug effects / Q000502:physiology*; D007038:Hypotonic Solutions / Q000494:pharmacology; D008954:Models, Biological; D009399:Nephrons / Q000187:drug effects / Q000502:physiology; D009997:Osmotic Pressure / Q000187:drug effects; D014882:Water-Electrolyte Balance / Q000187:drug effects / Q000502:physiology*; D014982:Xenopus laevis
D007038:Hypotonic Solutions; D000255:Adenosine Triphosphate; D002118:Calcium