Does intracellular histamine mediate mast cell histamine release?

Influence of DPPE on histamine release from isolated rat mast cells

“…The release induced by the ionophore A23187 can be enhanced or inhibited or both, depending on the magnitude of the ionophore response, whereas the influence of DPPE on responses to a combination of the phorbol ester TPA and a very low concentration of the ionophore is variable but small. The ability of DPPE to inhibit mast cell responses to antigen is in agreement with observations with concanavalin A [5] but its potency is somewhat lower than that reported against concanavalin A (IC5o of 70 gM vs. 30 gM [5]). The inhibition is dependent on preincubation and does not seem to be due to toxic effects on oxidative energy production as judged from the marginal effect of including glucose in the medium.…”

“…The ability of DPPE to inhibit concanavalin A-induced histamine release led to an extension of this hypothesis to cover mast cells [5]. According to this, DPPE would, however, be expected to inhibit not only IgE-directed secretagogues, e.g.…”

“…In mast cells the ability of DPPE to inhibit the histamine release induced by concanavalin A has likewise been taken as support for a messenger function for histamine [5]. With the aim of investigating whether such a DPPE-sensitive target is of common importance for mast cell responses we have studied the influence of DPPE on histamine release induced by a selection of secretagogues which are considered to employ different mechanisms.…”