Question

This is my part of the question in my groups pathophysiology case study.!

4. Mechanism of action of the albuterol, and other asthma treatments available and how they work ( singulair, Advair, pulmicort, flovent), and how a physician may decide to prescribe certain medications over others for particular patients

Answer 1

Albuterol is a selective beta2-adrenergic receptor agonist with pharmacological properties and therapeutic indications similar to terbutaline. The mechanism of the antiasthmatic action of beta-adrenergic receptor agonists is undoubtedly linked to the direct relaxation of airway smooth muscle and consequent bronchodilation. Although human bronchial smooth muscle receives little or no sympathetic innervations, it nevertheless contains large numbers of beta2-adrenergic receptors. Stimulation of these receptors activates the Gs adenylyl cyclase cyclic AMP pathway with consequent reduction in smooth muscle tone. Beta2-adrenergic receptor agonist (e.g. albuterol, isoproterenol) also increase the conductance of large Ca2+-sensitive K+ channels in airway smooth muscle, leading to membrane hyperpolerization and relaxation.

Singulair is a CysLT1antagonist; it blocks the action of leukotrieneD4 (and secondary ligands LTC4 and LTE4) on the cysteinyl leukotriene receptor CysLT1 in the lungs and bronchial tubes by binding to it. This reduces the bronchoconstrictionotherwise caused by the leukotriene and results in less inflammation.
Advair, a corticosteroid, is the anti-inflammatory component of the combination, while salmeterol, a long acting beta-adrenoceptor agonist (LABA), treats constriction of the airways. Together, they help prevent symptoms of coughing, wheezing and shortness of breath.
Pulmicort is an agonist of glucocorticoid receptors. Among its effects are:

Controls the rate of protein synthesis.Depresses the migration of polymorphonuclear leukocytes and fibroblasts.Reverses capillary permeability and lysosomal stabilization at the cellular level to prevent or control inflammation.Has a potent glucocorticoid activity and weak mineralocorticoid activity.
Flovent is a highly selective agonist at the glucocorticoid receptor with negligible activity at androgen, estrogen, or mineralocorticoid receptors, thereby producing anti-inflammatory and vasoconstriction effects.