Structure and dynamics of the fusion pores in live GH-secreting cells revealed using atomic force microscopy.
Earlier studies in live pancreatic acinar cells identified new cellular structures at the cell plasma membrane called 'pits' and 'depressions', where membrane-bound secretory vesicles dock and fuse to release vesicular contents. In the current study, using atomic force microscopy we identify similar structures at the plasma membrane of GH-secreting cells of the pituitary and implicate their involvement in hormone release. Pits containing 100-200 nm in diameter depressions or fusion pores were identified in resting GH-secreting cells. Following stimulation of secretion the size of depression enlarged and gold-tagged GH antibody were found to bind to the pit structures in the stimulated GH cells. This study documents for the first time the presence of these structures and their involvement in secretions in a neuroendocrine cell.
Cho
Sang-Joon
SJ
Department of Physiology, Wayne State University, School of Medicine, Detroit, Michigan 48201, USA.
Jeftinija
Ksenija
K
Glavaski
Aleksandra
A
Jeftinija
Srdija
S
Jena
Bhanu P
BP
Anderson
Lloyd L
LL
D000199:Actins / Q000378:metabolism; D000818:Animals; D002469:Cell Separation; D013006:Growth Hormone / Q000378:metabolism*; D006462:Hemolytic Plaque Technique; D007150:Immunohistochemistry; D018625:Microscopy, Atomic Force; D009490:Neurosecretory Systems / Q000166:cytology / Q000378:metabolism; D010902:Pituitary Gland / Q000166:cytology / Q000378:metabolism* / Q000648:ultrastructure*; D013552:Swine; D016707:Tissue Fixation
D000199:Actins; D013006:Growth Hormone