Differential quantal release of histamine and 5-hydroxytryptamine from mast cells of vesicular monoamine transporter 2 knockout mice.


Journal Article

The recent availability of mice lacking the neuronal form of the vesicular monoamine transporter 2 (VMAT2) affords the opportunity to study its roles in storage and release. Carbon fiber microelectrodes were used to measure individual secretory events of histamine and 5-hydroxytryptamine (5-HT) from VMAT2-expressing mast cells as a model system for quantal release. VMAT2 is indispensable for monoamine storage because mast cells from homozygous (VMAT2(-/-)) mice, while undergoing granule-cell fusion, do not release monoamines. Cells from heterozygous animals (VMAT2(+/-)) secrete lower amounts of monoamine per granule than cells from wild-type controls. Investigation of corelease of histamine and 5-HT from granules in VMAT2(+/-) cells revealed 5-HT quantal size was reduced more than that of histamine. Thus, although vesicular transport is the limiting factor determining quantal size of 5-HT and histamine release, intragranular association with the heparin matrix also plays a significant role.

Full Text

Duke Authors

Cited Authors

  • Travis, ER; Wang, YM; Michael, DJ; Caron, MG; Wightman, RM

Published Date

  • January 4, 2000

Published In

Volume / Issue

  • 97 / 1

Start / End Page

  • 162 - 167

PubMed ID

  • 10618388

Pubmed Central ID

  • 10618388

International Standard Serial Number (ISSN)

  • 0027-8424

Digital Object Identifier (DOI)

  • 10.1073/pnas.97.1.162


  • eng

Conference Location

  • United States