Storage and Release of Noradrenaline in Hypothalamic Synaptosomes

Abstract
The noradrenaline [norepinephrine] storage capacity of vesicles in rat hypothalamic synaptosomes was measured by incubating them with [3H]noradrenaline under saturating conditions. The normal noradrenaline content was 52% of storage capacity. Incubation or superfusion with 50 mM-K cause Ca-dependent release from the vesicles. Release reduced the vesicular content and the noradrenaline storage capacity. After exocytosis, vesicles apparently cannot refill with noradrenaline.