Exocytosis-removal Cycle of Single Secretory Granules Visualized by Confocal Laser Microscopy

• Segawa Akihisa

  Department of Anatomy, School of Medicine, Kitasato University

Abstract

Exocytotic secretion entails the cycles of fusion and removal of secretory granule membranes at the cell surface (exocytosis-removal cycle), occurring at proper sites and proper timing. Attempts were made to visualize these processes directly in living rat parotid acinar cells, by flooding the exocytosed granule space with fluid-phase fluorescent tracers (Lucifer yellow or FITC-dextrans) and by imaging its changes with confocal microscopy. With a delay of 10～15 seconds after addition of isoproterenol to stimulate secretion, exocytotic profiles, as indicated by the fluorescent spots, appeared along the luminal border abruptly in a granule-shape. Such profiles maintained their round shape for periods ranging from a few seconds to several tens of seconds, then gradually diminished and disappeared within a total time range of between 40 and 70 seconds. These images probably represent the spatio-temporal events involved in the exocytosis-removal cycle of single secretory granules, including stimulus-secretion coupling and exocytosis-endocytosis coupling, as indicated previously by biochemical and electrophysiological studies.

Journal

• bioimages

  bioimages 5 (4), 153-155, 1997

  Bioimaging Society

Keywords

• stimulus-secretion coupling
• exocytosis-endocytosis coupling
• confocal microscopy
• fluorescent tracer
• salivary gland

Details

• CRID: 1390007857410301568
• NII Article ID: 10002038393
• NII Book ID: AA11084187
• DOI: 10.11169/bioimages.5.153
• ISSN: 09192719
• Text Lang: en
• Data Source:
  • JaLC
  • CiNii Articles
• Abstract License Flag: Disallowed