Physical mobilization of secretory vesicles facilitates neuropeptide release by nerve growth factor-differentiated PC12 cells

J Physiol. 2002 Jul 15;542(Pt 2):395-402. doi: 10.1113/jphysiol.2002.021733.

Abstract

It has been speculated that neurosecretion can be enhanced by increasing the motion, and hence, the availability of cytoplasmic secretory vesicles. However, facilitator-induced physical mobilization of secretory vesicles has not been observed directly in living cells, and recent experimental results call this hypothesis into question. Here, high resolution green fluorescent protein (GFP)-based measurements in nerve growth factor-differentiated PC12 cells are used to test whether altering dense core vesicle (DCV) motion affects neuropeptide release. Experiments with mycalolide B and jasplakinolide demonstrate that neuropeptidergic DCV motion at the ends of processes is proportional to F-actin. Furthermore, Ba2+ increases DCV mobility without detectably modifying F-actin. Finally, we show that altering DCV motion by changing F-actin or stimulating with Ba2+ proportionally changes sustained neuropeptide release. Therefore, increasing DCV mobility facilitates prolonged neuropeptide release.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Actins / drug effects
  • Actins / physiology*
  • Animals
  • Antineoplastic Agents / pharmacology
  • Cell Differentiation / drug effects*
  • Depsipeptides*
  • Genes, Reporter
  • Green Fluorescent Proteins
  • Luminescent Proteins / metabolism
  • Marine Toxins
  • Movement
  • Nerve Growth Factor / pharmacology*
  • Neuropeptides / metabolism*
  • Oxazoles / pharmacology
  • PC12 Cells
  • Peptides, Cyclic / pharmacology
  • Pheochromocytoma
  • Rats
  • Recombinant Proteins / metabolism
  • Secretory Vesicles / drug effects
  • Secretory Vesicles / physiology*
  • Secretory Vesicles / ultrastructure

Substances

  • Actins
  • Antineoplastic Agents
  • Depsipeptides
  • Luminescent Proteins
  • Marine Toxins
  • Neuropeptides
  • Oxazoles
  • Peptides, Cyclic
  • Recombinant Proteins
  • jasplakinolide
  • mycalolide B
  • Green Fluorescent Proteins
  • Nerve Growth Factor