Abstract
We have used quick-freezing and freeze-fracture to study early stages of exocytosis in rat peritoneal mast cells. Mast cells briefly stimulated with 48/80 (a synthetic polycation and well-known histamine-releasing agent) at 22°C displayed single, narrow-necked pores (some as small as 0.05 μm in diameter) joining single granules with the plasma membrane. Pores that had become as large as 0.1 μm in diameter were clearly etchable and thus represented aqueous channels connecting the granule interior with the extracellular space. Granules exhibiting pores usually did not have wide areas of contact with the plasma membrane, and clearings of intramembrane particles, seen in chemically fixed mast cells undergoing exocytosis, were not present on either plasma or granule membranes. Fusion of interior granules later in the secretory process also appeared to involve pores; granules were often joined by one pore or a group of 2-4 pores. Also found were groups of extremely small, etchable pores on granule membranes that may represent the earliest aqueous communication between fusing granules.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 666-674 |
| Number of pages | 9 |
| Journal | Journal of Cell Biology |
| Volume | 86 |
| Issue number | 2 |
| State | Published - 1980 |
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ASJC Scopus subject areas
- Cell Biology
Cite this
Arrest of membrane fusion events in mast cells by quick-freezing. / Chandler, D. E.; Heuser, J. E.
In: Journal of Cell Biology, Vol. 86, No. 2, 1980, p. 666-674.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Arrest of membrane fusion events in mast cells by quick-freezing
AU - Chandler, D. E.
AU - Heuser, J. E.
PY - 1980
Y1 - 1980
N2 - We have used quick-freezing and freeze-fracture to study early stages of exocytosis in rat peritoneal mast cells. Mast cells briefly stimulated with 48/80 (a synthetic polycation and well-known histamine-releasing agent) at 22°C displayed single, narrow-necked pores (some as small as 0.05 μm in diameter) joining single granules with the plasma membrane. Pores that had become as large as 0.1 μm in diameter were clearly etchable and thus represented aqueous channels connecting the granule interior with the extracellular space. Granules exhibiting pores usually did not have wide areas of contact with the plasma membrane, and clearings of intramembrane particles, seen in chemically fixed mast cells undergoing exocytosis, were not present on either plasma or granule membranes. Fusion of interior granules later in the secretory process also appeared to involve pores; granules were often joined by one pore or a group of 2-4 pores. Also found were groups of extremely small, etchable pores on granule membranes that may represent the earliest aqueous communication between fusing granules.
AB - We have used quick-freezing and freeze-fracture to study early stages of exocytosis in rat peritoneal mast cells. Mast cells briefly stimulated with 48/80 (a synthetic polycation and well-known histamine-releasing agent) at 22°C displayed single, narrow-necked pores (some as small as 0.05 μm in diameter) joining single granules with the plasma membrane. Pores that had become as large as 0.1 μm in diameter were clearly etchable and thus represented aqueous channels connecting the granule interior with the extracellular space. Granules exhibiting pores usually did not have wide areas of contact with the plasma membrane, and clearings of intramembrane particles, seen in chemically fixed mast cells undergoing exocytosis, were not present on either plasma or granule membranes. Fusion of interior granules later in the secretory process also appeared to involve pores; granules were often joined by one pore or a group of 2-4 pores. Also found were groups of extremely small, etchable pores on granule membranes that may represent the earliest aqueous communication between fusing granules.
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UR - http://www.scopus.com/inward/citedby.url?scp=0019305230&partnerID=8YFLogxK
M3 - Article
C2 - 7400221
AN - SCOPUS:0019305230
VL - 86
SP - 666
EP - 674
JO - Journal of Cell Biology
JF - Journal of Cell Biology
SN - 0021-9525
IS - 2
ER -