NCIt definition : The sulfate salt form of metaproterenol, a short-acting and selective sympathomimetic
beta-receptor agonist with bronchodilator activity. Metaproterenol sulfate binds beta-2
adrenergic receptors in bronchial smooth muscle and stimulates intracellular adenyl
cyclase, thereby increasing the production of cyclic adenosine monophosphate (cAMP).
Increased cAMP levels cause relaxation of bronchial smooth muscle, improve mucocliary
clearance and reduce inflammatory cell mediator release, especially from mast cells.;