Computation of Pump-Leak Flux Balance in Animal Cells

Cellular Physiology and Biochemistry

关键词: Channels;    Ion fluxes;    Cell ion balance;    Cell water balance;    Ion transport;    Cotransport;    Sodium pump;   

DOI  :  10.1159/000366382

学科分类：分子生物学，细胞生物学和基因

来源: S Karger AG

【 摘 要 】

Background/Aims Many vital processes in animal cells depend on monovalent ion transport across the plasma membrane via specific pathways. Their operation is described by a set of nonlinear and transcendental equations that cannot be solved analytically. Previous computations had been optimized for certain cell types and included parameters whose experimental determination can be challenging. Methods We have developed a simpler and a more universal computational approach by using fewer kinetic parameters derived from the data related to cell balanced state. A file is provided for calculating unidirectional Na⁺, K⁺, and Cl^- fluxes via all major pathways (i.e. the Na/K pump, Na⁺, K⁺, Cl^- channels, and NKCC, KC and NC cotransporters) under a balanced state and during transient processes. Results The data on the Na⁺, K⁺, and Cl^- distribution and the pump flux of K⁺ (Rb⁺) are obtained on U937 cells before and after inhibiting the pump with ouabain. There was a good match between the results of calculations and the experimentally measured dynamics of ion redistribution caused by blocking the pump. Conclusion The presented approach can serve as an effective tool for analyzing monovalent ion transport in the whole cell, determination of the rate coefficients for ion transfer via major pathways and studying their alteration under various conditions.

【 授权许可】

CC BY-NC-ND