title: [A mathematical model of the regulation mechanism of Ca2+ concentration in lens in vivo].
abstract: In order to elucidate the regulation mechanism of homeostasis on intracellular Ca2+ concentration in lens in vivo, the authors proposed a new mathematical model based upon the model of Ca2+ active transport. The mathematical model has new factors: Ca2+ efflux and Ca2+ influx across the cell membrane related to the difference between intracellular and extracellular Ca2+ concentration. Changes in intracellular Ca2+ concentration were investigated by numerical simulation using this model. Ca2+ efflux (active transport) is increased with intracellular Ca2+ concentration and their relationship corresponds to a Michaelis-Menten reaction. Ca2+ influx increases with the Ca2+ permeable coefficient of cell membrane. These results are consistent with the experimental results is a qualitative way and indicate that the model is suitable to elucidate the regulation mechanism of intracellular Ca2+ concentration. From the theoretical point of view, therefore, it is suggested that intracellular Ca2+ concentration may depend on two factors: one is the Ca2+ dependence of the Ca2+ active transport system, the other the Ca2+ permeability of the cell membrane.
authors.affiliation: Department of Ophthalmology, Medical College of Oita, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Imaizumi
authors.forename: M
authors.initials: M
authors.lastname: Furushima
authors.forename: K
authors.initials: K
authors.lastname: Nakatsuka
authors.forename: U
authors.initials: U
authors.lastname: Yamanouchi
mesh_terms: D002118:Calcium / Q000378:metabolism*; D006706:Homeostasis; D006801:Humans; D007908:Lens, Crystalline / Q000378:metabolism*; D008433:Mathematics; D008954:Models, Biological
chemical_list: D002118:Calcium