The Hypertonic State

Abstract

Evolution has provided an elaborate network of regulatory systems that stabilize body-fluid volume, temperature and composition. This stability insulates cells from an ambient hostile world and assures them the best possible conditions in which to function optimally. When one of these regulatory systems fails, cells and even whole organ systems cannot function properly. This paper discusses what goes wrong when body fluids become too concentrated.Cell membranes are more or less impermeable to most solutes but freely permeable to water so that intracellular-fluid and extracellular-fluid osmolality equalizes despite very different composition (Fig. 1). The major osmotic solutes in intracellular fluid . . .