Erratum to: Mathematical properties of pump-leak models of cell volume control and electrolyte balance

Abstract

Homeostatic control of cell volume and intracellular electrolyte content is a fundamental problem in physiology and is central to the functioning of epithelial systems. These physiological processes are modeled using pump-leak models, a system of differential algebraic equations that describes the balance of ions and water flowing across the cell membrane. Despite their widespread use, very little is known about their mathematical properties. Here, we establish analytical results on the existence and stability of steady states for a general class of pump-leak models. We treat two cases. When the ion channel currents have a linear current-voltage relationship, we show that there is at most one steady state, and that the steady state is globally asymptotically stable. If there are no steady states, the cell volume tends to infinity with time. When minimal assumptions are placed on the properties of ion channel currents, we show that there is an asymptotically stable steady state so long as the pump current is not too large. The key analytical tool is a free energy relation satisfied by a general class of pump-leak models, which can be used as a Lyapunov function to study stability.Keywords Cell volume control · Electrolyte balance · Free energy · Lyapunov function · Differential algebraic systemDue to typographical errors inadvertently introduced into the orignal manuscript during the publisher's production process, the original publication is incorrect. The complete and correct version is given here.The online version of the original article can be found under