Abstract
Light noradrenaline [norepinephrine] storage vesicles from nerve endings were isolated by differential centrifugation and differential gradient centrifugation. They were further purified by isopycnic sucrose/D2O centrifugation. By using these centrifugation techniques, an isopycnic gradient fraction was observed in which noradrenaline was enriched .apprx. 41 times vs. a total homogenate. This factor could be raised to 61 by using seminal ducts of castrated rats. Comparison of the distribution patterns in sucrose/D2O isopycnic gradients indicated that light noradrenaline vesicles of nerve endings contain Mg2+-stimulated ATPase and ATP, but that only a minor part of the dopamine .beta.-hydroxylase can be associated with these vesicles.