The effect of beta-adrenoceptor blocking drugs on histamine liberation, prostaglandin synthesis and phospholipid turnover in isolated mast cells stimulated with concanavalin A.

Exaprolol, metipranolol and propranolol decreased significantly histamine liberation, degranulation, 45Ca uptake and thromboxane B2 formation in isolated rat mast cells stimulated with concanavalin A and phosphatidylserine. Moreover, exaprolol and metipranolol decreased 32P incorporation into membrane phospholipids and metipranolol and propranolol reduced the liberation of arachidonic acid from membrane phospholipids of stimulated mast cells. Exaprolol significantly increased the arachidonic acid liberation from these cells. Possible mechanisms of interaction of beta-adrenoceptor blocking drugs with isolated mast cells are discussed.