Isoetharine
Isoetharine is a beta-adrenergic receptor agonist with bronchodilator activity. Isoetharine selectively binds to beta-2 adrenergic receptors in bronchial smooth muscle, thereby activating intracellular adenyl cyclase, an enzyme that catalyzes the conversion of adenosine triphosphate (ATP) to cyclic-3',5'-adenosine monophosphate (cAMP). Increased cAMP levels cause relaxation of bronchial smooth muscle, relieve bronchospasms, improve mucociliary clearance and reduce mediator substance release from inflammatory cells, especially from mast cells.