Isolation of mouse chromaffin secretory vesicles and their division into 12 fractions

- We present a method to obtain high-yields of purified secretory vesicles from mouse chromaffin cells under isotonic conditions.
- We describe their further separation into 12 fractions and the analysis of the content of each fraction.
- These isolated vesicles retain the ability to take up catecholamines.

The study of chromaffin secretory vesicles (SVs) has contributed immensely to our understanding of exocytosis. These organelles, also called chromaffin granules, are a specific type of large dense secretory vesicle found in many endocrine cells and neurons. Traditionally, they have been isolated from bovine adrenal glands due to the large number of SVs that can be obtained from this tissue. However, technical advances now make it possible to obtain very pure preparations of SVs from mice, which is particular interesting for functional studies given the availability of different genetically modified strains of mice. Despite the small size of the mouse adrenal medulla (400-500 μm and less than 2 mg in weight), we have successfully carried out functional studies on SVs isolated from WT and knockout mice. As such, we present here our method to purify crude vesicles and to fractionate mouse chromaffin SVs, along with examples of their functional characterization.