Chromaffin Versus Platelet Granules: What We Have Learned From Chromaffin Cells for Human Studies

Biological amines-such as dopamine, norepinephrine, epinephrine, octopamine, serotonin, and histamine-are stored at high concentrations within secretory vesicles, also referred to as "granules" in certain cell types, including mast cells, chromaffin cells, and platelets. Over the past decades, extensive knowledge has been gained regarding the biogenesis, composition, and function of chromaffin granules. This information can now be leveraged to understand amine storage mechanisms in other secretory systems, particularly in human platelets, which are readily accessible. Importantly, dysfunction of secretory vesicles has been implicated in several diseases, and vesicular defects may therefore be detectable in platelets obtained from well-characterized individuals. Such an approach offers significant potential for clinical and translational studies, as personalized functional information can be directly derived from patients. In this brief review, I focus on the vesicular mechanisms involved in biological amine accumulation and discuss the functional consequences of their disruption, with particular emphasis on chromaffin granules and platelet δ-granules.