Intravital Microscopy and Its Application to Study Regulated Exocytosis in the Exocrine Glands of Live Rodents

Regulated exocytosis is a fundamental event in specialized secretory organs that has been primarily studied in in vitro and ex vivo model systems. The recent application of intravital microscopy to image subcellular structures in vivo has enabled researchers to investigate the machinery controlling regulated exocytosis in live rodents. Here, we describe selected experimental models that have been used to investigate the dynamics of the secretory granules after their initial fusion their with the plasma membrane. Specifically, we used rodent salivary glands, an established model for exocrine secretion. Our goal is to provide the reader with guidelines on how to apply both qualitative and quantitative intravital microscopy to study regulated exocytosis and to highlight advantages and limitations of this approach.