Part of “CHAPTER 3 – BIOSYNTHESIS AND SECRETION OF PEPTIDE HORMONES“

Secretory granules release their contents by cytoskeletal protein-mediated movement of the granule toward the cellular surface.61a There, secretory granule membranes fuse with the plasma membrane and allow eversion or exocytosis of stored hormone.62 This process of emiocytosis causes secretion of hormone. The mechanisms involved in stimulus-secretion coupling are not well known, although responses to cellular signals causing changes in intracellular calcium, ion currents, or intra-cellular pH may lead to these events.