Dissection of Two Types of Triggered Endocytosis in Chromaffin Cells

Wayne State University, Detroit MI

Investigators

Abstract

9985874 Artajelo Secretion is n important property of virtually all cells in the body, but to certain cell types like neurons and neutoendoctrine cells it is one of their primary functions. For example, chromaffin cells of the adrenal medulla secrete catecholamines into the blood stream and comprise a large part of the "fight-or-flight response whereby most vertebrates including humans prepare themselves for escape or respond to other stresses. In cells highly adapted for secretion the intracellular secretory vesicles recycle many times. This essential function enables the cells to secrete on a continuous basis which is critical for communication with other cells. The first step in recycling is the recapture of the vesicular membrane from the cell surface. The mechanism of this endocytotic process has been debated for many years but is still unsolved. We have described a novel rapid endocytotic mechanism in chromaffin cells that may be the main mechanism both kinetic and molecular experiments will be perform to attain a detailed understanding of the two processes. These studies will contribute to our understanding of vesicle recycling in all cells that undergo regulated secretion, including neurons.