Brain Edema, Electrolytes, and Extracellular Space

Abstract

During the course of a number of studies of the blood-brain barrier, the urgent need for good physiological measurements of the size of the functional compartments (extracellular space, glial space, neuronal space, etc) of the central nervous system became apparent. In one of these studies the volume of distribution of sucrose in the CNS was investigated. It was observed that sucrose distributed in two compartments of the brain at markedly different rates. On this basis it was suggested that the compartment with the shortest half-time for sucrose entry was the extracellular space and that the other compartment was the intracellular, composed of one or more cell types, possibly glial cells.¹⁴ Triethyl tin (TET) in very small quantities causes cerebral edema, shown by Torack et al¹⁹ to be confined to the glial cells although other workers have suggested that TET edema is extracellular.¹¹ Luse and Harris¹⁰ have