These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: IgE-mediated degranulation of mast cells does not require opening of ion channels. Author: Lindau M, Fernandez JM. Journal: Nature; ; 319(6049):150-3. PubMed ID: 2417125. Abstract: Rat peritoneal mast cells respond to antigenic stimulation by releasing histamine through exocytosis. The dynamics of exocytosis can be investigated by dialysing single cells with patch pipettes using the whole-cell recording configuration of the patch-clamp technique. However, dialysed cells fail to respond to external stimuli such as compound 48/80 or antigens, suggesting that essential cytoplasmic components have been washed out. We have developed a new patch-clamp configuration in which the patch under the pipette tip is not disrupted but instead permeabilized, preventing the diffusion of large molecules out of the cell. In this configuration the cell responds to external stimulation, and the capacitance as well as the conductance of the cell membrane can be recorded during degranulation. On antigenic stimulation, the cell capacitance (proportional to plasma membrane area), after an initial delay, increases by a factor of about 3. This increase in capacitance is often preceded by a transient increase in conductance. Agents that block Ca-activated channels inhibit this conductance change without affecting the amplitude and time course of degranulation. We therefore conclude that, in contrast to excitable secretory cells such as chromaffin cells, mast cells do not use ion channels in stimulus-secretion coupling.[Abstract] [Full Text] [Related] [New Search]