NR3C1 and chronic obstructive pulmonary disease: Corticosteroids increase the numbers of β2 ARs, whereas β2 agonists induce direct bronchodilation and increase glucocorticoid receptor (GR) nuclear translocation in the presence of corticosteroids, an effect that enhances the anti-inflammatory effects of corticosteroids and also occurs in COPD macrophages that are quite resistant to corticosteroids.