The relation between degranulation and rapid metabolic responses in RBL-2H3 cells

The relation between degranulation and rapid metabolic responses (acidification rate changes) in RBL-2H3 cells was studied using a cytosensor microphysiometer, a silicon-based biosensor system. The metabolic responses in RBL-2H3 cells by antigen stimulation were compared with those by inhibitors of Ca2+ -ATPase. The former resulted in a rapid transient increase in the acidification rate of RBL-2H3 cells while the latter resulted in gradual decreases. When RBL-2H3 cells were costimulated with the inhibitors of Ca2+ -ATPase and an activator (PMA, phorbol-12-myristoyl-13-acetate) of protein kinase C, the metabolic responses increased again in RBL-2H3 cells. This seems to indicate that degranulation in RBL-2H3 cells was accelerated by costimulation with the inhibitors and PMA. However, costimulation was not able to completely mimic the way antigen stimulated RBL-2H3 cells in degranulation and in rapid metabolic responses.