Role of cyclic AMP in the induction of histamine secretion from mast cells

Immunological activation of rat peritoneal mast cells induced a transient elevation in the intracellular concentration of cyclic AMP. Enhancement or suppression of this rise by appropriate adenosine analogues produced parallel changes in histamine secretion. However, pharmacological activation of the cell with a number of diverse ligands induced histamine release without any accompanying changes in cyclic AMP. Moreover, this release was modulated by adenosine analogues in identical fashion to IGE-directed ligands but again without affecting cyclic AMP. On the basis of these results, the possible role of cyclic AMP in the induction of histamine secretion is critically considered.