Adrenaline and Salbutamol Rapidly Exert Mast Cell-Stabilizing Properties in Rat Peritoneal Mast Cells

Adrenaline is the first-choice drug for the treatment of anaphylaxis. Previous studies have revealed its prophylactic effects on the release of chemical mediators from mast cells. However, adrenaline quickly reverses the symptoms and signs of anaphylaxis after injection, indicating its rapid effects on mast cells.

We examined the effects of adrenaline on rat peritoneal mast cell degranulation using differential-interference contrast (DIC) microscopy. To examine the rapid effects of adrenaline and salbutamol, a selective β2-adrenergic receptor agonist, we treated mast cells with these drugs immediately after exocytosis induction.

Similar to mast cells pre-incubated with adrenaline, those immediately treated with adrenaline did not exhibit exocytosis. At concentrations equal to or higher than 0.2 mg/ml, adrenaline significantly reduced the numbers of degranulating mast cells in a dose-dependent manner, whereas salbutamol required higher doses to exert significant effects. At 1 mg/ml, adrenaline and salbutamol almost completely suppressed mast cell degranulation.

This study provides novel in vitro evidence indicating for the first time that adrenaline rapidly exerts mast cell-stabilizing properties in a dose-dependent manner. Salbutamol also stabilizes mast cells at high doses, revealing its additive therapeutic efficacy in anaphylaxis management.