Lund University is celebrating 350 years. Read more on lunduniversity.lu.se

Menu

Javascript is not activated in your browser. This website needs javascript activated to work properly.
You are here

Delay between fusion pore opening and peptide release from large dense-core vesicles in neuroendocrine cells.

Author:
  • Sebastian Barg
  • Charlotta Olofsson
  • Jenny Schriever-Abeln
  • Anna Wendt
  • Samuel Gebre-Medhin
  • Erik Renström
  • Patrik Rorsman
Publishing year: 2002
Language: English
Pages: 287-299
Publication/Series: Neuron
Volume: 33
Issue: 2
Document type: Journal article
Publisher: Cell Press

Abstract english

Peptidergic neurotransmission is slow compared to that mediated by classical neurotransmitters. We have studied exocytotic membrane fusion and cargo release by simultaneous capacitance measurements and confocal imaging of single secretory vesicles in neuroendocrine cells. Depletion of the readily releasable pool (RRP) correlated with exocytosis of 10%-20% of the docked vesicles. Some remaining vesicles became releasable after recovery of RRP. Expansion of the fusion pore, seen as an increase in luminal pH, occurred after approximately 0.3 s, and peptide release was delayed by another 1-10 s. We conclude that (1) RRP refilling involves chemical modification of vesicles already in place, (2) the release of large neuropeptides via the fusion pore is negligible and only proceeds after complete fusion, and (3) sluggish peptidergic transmission reflects the time course of vesicle emptying.

Keywords

  • Neurosciences
  • Peptides/*metabolism
  • PC12 Cells
  • Neurosecretory Systems/cytology/*metabolism
  • Membrane Fusion/*physiology
  • Luminescent Proteins
  • Kinetics
  • Indicators and Reagents
  • Hydrogen-Ion Concentration
  • Exocytosis/*physiology
  • Fluorescence
  • Rats
  • Secretory Vesicles/*metabolism
  • Support
  • Non-U.S. Gov't
  • Electric Stimulation
  • Cell Line
  • Animal

Other

Published
  • Islet cell physiology
  • Islet cell exocytosis
  • ISSN: 0896-6273
Erik Renström
E-mail: erik.renstrom [at] med.lu.se

Deputy head of department

Department of Clinical Sciences, Malmö

+46 40 39 11 57

+46 40 39 11 57

Principal investigator

Islet patophysiology

+46 40 39 11 57

+46 40 39 11 57

20-3-308

33

Lund University Diabetes Centre, CRC, SUS Malmö, Entrance 72, House 91:12. SE-205 02 Malmö. Telephone: +46 40 39 10 00