Nanoscale Amperometry Reveals that Only a Fraction of Vesicular Serotonin Content is Released During Exocytosis from Beta Cells

Recent work has shown that chemical release during the fundamental cellular process of exocytosis in model cell lines is not all-or-none. We tested this theory for vesicular from single pancreatic beta cells. The vesicles these cells insulin, but also serotonin, which detectible with amperometric methods. Traditionally, it assumed Here, we use a multidisciplinary approach involving nanoscale methods to explore nature insulin exocytosis. amperometrically quantified number serotonin molecules stored inside individual (39 317±1611) cytoplasm before and released (13 310±1127) each stimulated event. Thus, only one-third their granule content, clearly supporting partial system. discuss observations context type-2 diabetes.