title: Modelisation of the contribution of the Na/Ca exchanger to cell membrane potential and intracellular ion concentrations.
abstract: Modelisation plays a significant role in the study of ion transfer through the cell membrane and in the comprehension of cellular excitability. We were interested in the selective ion transfers through the K(Ca), Na(v), Ca(v) channels and the Na/Ca exchanger (NCX). The membrane behaves like an electric circuit because of the existence of ion gradients maintained by the cell. The non-linearity of this circuit gives rise to complex oscillations of the membrane potential. By application of the finite difference method (FDM) and the concept of percolation we studied the role of the NCX in the regulation of the intracellular Ca(2+) concentration and the oscillations of the membrane potential. The fractal representation of the distribution of active channels allows us to follow the diffusion of intracellular Ca(2+) ions. These calculations show that the hyperpolarization and the change in the burst duration of the membrane potential are primarily due to the NCX.
authors.affiliation: Laboratoire de Physique des Plasmas, Matériaux Conducteurs et leurs Applications, Département de Physique, USTO'MB, BP 1505, Al Menouer Oran, Algeria. ba_samia@hotmail.com
authors.forename: S
authors.initials: S
authors.lastname: Bahlouli
authors.forename: F
authors.initials: F
authors.lastname: Hamdache
authors.forename: H
authors.initials: H
authors.lastname: Riane
mesh_terms: D002118:Calcium / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism*; D004553:Electric Conductivity; D042541:Intracellular Space / Q000378:metabolism*; D008564:Membrane Potentials; D008954:Models, Biological; D018408:Patch-Clamp Techniques; D019831:Sodium-Calcium Exchanger / Q000378:metabolism*
chemical_list: D019831:Sodium-Calcium Exchanger; D002118:Calcium