Fig. 6.

Membrane-bound glucocorticoid receptors exist in human airway smooth muscle (HASM). A: HASM from lung donors without disease was biotinylated, and purification of a membrane fraction determined the existence of a membrane-bound form of the glucocorticoid receptor. Presence of the epidermal growth factor receptor (EGFR) and absence of GAPDH; cytochrome c oxidase (COX) IV (cytosolic proteins) were used as controls for purity of membrane protein isolation. B: HASM cells were fixed with acetone following stimulation for 30 min with dexamethasone (1 μM). Fixed cells were then probed for glucocorticoid receptor and DAPI. Data are representative of three separate donors without asthma for both A and B.