Differential quantal release of histamine and 5-hydroxytryptamine from mast cells of vesicular monoamine transporter 2 knockout mice
AUTOR(ES)
Travis, Eric R.
FONTE
The National Academy of Sciences
RESUMO
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.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=26633Documentos Relacionados
- The effects of substance P on histamine and 5-hydroxytryptamine release in the rat
- Normal Biogenesis and Cycling of Empty Synaptic Vesicles in Dopamine Neurons of Vesicular Monoamine Transporter 2 Knockout Mice
- Attenuated hypoxic pulmonary hypertension in mice lacking the 5-hydroxytryptamine transporter gene
- HISTAMINE AND 5-HYDROXYTRYPTAMINE IN THE BLOOD OF INFANTS AND CHILDREN
- Mechanical stimulation activates Gαq signaling pathways and 5-hydroxytryptamine release from human carcinoid BON cells