Construct | ISO | SAL | DOB | EPH | DCI |
---|---|---|---|---|---|
β2AR-GsαL | 1.7 ± 0.5 | 39 ± 23 | 90 ± 16 | 923 ± 270 | 13 ± 12 |
β2AR-GsαS | 6.2 ± 3.3 | 167 ± 78 | 310 ± 108 | 3600 ± 498 | 36 ± 15 |
β2AR-Giα2 | 31 ± 16 | 712 ± 401 | 1860 ± 890 | 1850 ± 500 | 15 ± 8 |
β2AR-Giα3 | 42 ± 18 | 809 ± 241 | 155 ± 90 | 917 ± 10 | —3-a |
β2AR-G16α | 143 ± 69 | 587 ± 311 | 595 ± 109 | 5990 ± 2130 | — |
β2AR-Gqα | 23 ± 13 | 310 ± 132 | 540 ± 211 | 4670 ± 1110 | — |
For determination of the potencies of ligands, GTPγS binding was measured in Sf9 membranes expressing β2AR-Gxα at 3.7 to 13.0 pmol/mg with 0.4 nM [35S]GTPγS as described under Experimental Procedures. The incubation time was 45 min. Reaction mixtures contained ligands at 0.1 nM to 1 mM as appropriate to obtain saturated concentration-response curves. The EC50 values are given in nM and were calculated by nonlinear regression. Data shown are the means ± S.D. values of three independent experiments performed in triplicates.
↵3-a —, DCI-stimulated GTPγS binding was too small to calculate an EC50 value.