Treatment β2 receptor agonists--albuterol β2 receptor agonists--albuterol activates adenylate cyclase activates adenylate cyclase increases cyclic adenosine monophosphate increases cyclic adenosine monophosphate bronchial smooth muscle relaxation bronchial smooth muscle relaxation binding intracellular calcium to endoplasmic reticulum binding intracellular calcium to endoplasmic reticulum