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Mast cell secretion: membrane events.

D Lagunoff·E Y Chi
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Abstract

Stimulation of secretion with A23187 circumvents the usual mechanism of stimulation of secretion by direct mediation of an increase in cytoplasmic Ca++ and thereby permits study of the terminal components of the secretory process in which granules are externalized by membrane fusion events. Two alterations in the plasma membrane precede fusion: the formation of bulges and the aggregation of intramembranous particles. These changes require a permissive level of ATP and are sensitive to reagents that bind to intracellular protein sulfhydryl groups. They seem not to be attributable to a direct effect of Ca++ on membrane phospholipids. The cell components responsive to Ca++ and responsible for the alterations in the membrane are not known; neither microtubules nor actin filaments seem to qualify.

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Adenosine TriphosphateAnimalsCalcimycinCell MembraneMast CellsRatsSecretory RateStimulation, ChemicalJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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D Lagunoff, E Y Chi. 1978. Mast cell secretion: membrane events.. https://doi.org/10.1111/1523-1747.ep12544430

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