Figure 5.

SC cells from different donors express variable levels of β₂AR protein and the β₂AR levels correlate with relaxation response to isoproterenol. (a) Western blot analysis of β₂AR in SC cells from five donors (see table 1 for donor information). Nearly identical results were obtained with technical duplicates. (b) The extent of cell relaxation in response to 1 µM isoproterenol (iso) positively correlates with the β₂AR levels (arb. units). % Relaxation was defined in §2, and relative β₂AR protein amount was quantified by densitometry and normalized to β-actin.