[Induction of granule release by intracellular application of Ca and GTP gamma S in human eosinophils]

Nihon Rinsho. 1993 Mar;51(3):620-5.
[Article in Japanese]

Abstract

The roles of Ca and G proteins in granule release from human eosinophils were examined using a patch-clamp technique in single cells. The morphological changes and the release of eosinophil peroxidase (EPO) from single cells were simultaneously observed. The intracellular application of Ca, and GTP-gamma-S induced fusion of EPO containing granules with the surface membrane which was associated with a marked increase in membrane capacitance. Ca alone caused a rapid granule release at an early stage of cell dialysis, but most granules still remained in a cluster. GTP-gamma-S alone caused a gradual degranulation. Northern blot analysis revealed the definite expression of smg p21 mRNA with no appreciable expression of smg p25A in human eosinophils.

MeSH terms

  • Calcium / pharmacology
  • Calcium / physiology*
  • Cell Degranulation / drug effects*
  • Cells, Cultured
  • Eosinophil Peroxidase
  • Eosinophils / enzymology
  • Eosinophils / metabolism
  • Eosinophils / physiology*
  • GTP-Binding Proteins / metabolism
  • GTP-Binding Proteins / physiology*
  • Humans
  • Peroxidases / metabolism
  • RNA, Messenger / analysis
  • rab3 GTP-Binding Proteins

Substances

  • RNA, Messenger
  • Eosinophil Peroxidase
  • Peroxidases
  • GTP-Binding Proteins
  • rab3 GTP-Binding Proteins
  • Calcium