Exocytosis (Secretory Granule Extrusion) Induced by Injection of Calcium into Mast Cells

Abstract

Injection of Ca (but not Mg or K) through micropipettes placed within rat peritoneal mast cells elicited extrusion of secretory granules. The result is considered direct support for the view that a rise in the intracellular concentration of Ca ions suffices to induce exocytosis and accounts for the general requirement for Ca in stimulus–secretion coupling.