Albuterol is an adrenergic receptor agonist with pharmacological properties and therapeutic indications similar to terbutaline. The mechanism of the anti-asthmatic action of adrenergic receptor agonists is without a doubt linked to the direct relaxation of airway smooth muscle and the bronchodilator. Although human bronchial smooth muscle receives little or no sympathetic stoppage, it contains large numbers of adrenergic receptors. When the adrenergic receptors activate the adenylyl cyclase cyclic AMP pathway it causes reduction in smooth muscle tone. Adrenergic receptor agonist for example, albuterol and isoproterenol, also increase the conductance of large Ca2+-sensitive K+ channels in airway smooth muscle, which then causes the membrane
