Reversible osmotic opening of the blood-brain barrier

Reversible breakdown of the blood-brain barrier is produced by a class of electrolytes and nonelectrolytes which have little or no lipid solubility but which difler in chemical and ionic properties. These agents may osmotically shrink barrier cells, possibly the vascular endothelium, and reversibly open spaces between them. Lipid-soluble nonelectrolytes damage the barrier irreversibly.