Dynamic extracellular space alters spatiotemporal distribution of chemical signals in brain

Abstract

Brain can be considered as a porous medium. The brain cells form a solid phase while the liquid-filled extracellular space (ECS) forms a porous phase that surrounds each individual cell. Brain ECS is of a fundamental importance for brain function [1]. It serves as a reservoir for ions and a channel for diffusion-mediated transport of biologically significant molecules and therapeutics. ECS volume is the main factor governing the extracellular concentrations of these substances. Any ECS volume change may lead to a change in concentration of ions and transported substances, and this has consequences for brain function