TABLE 3

CRE-SPAP and 3H-cAMP accumulation assays for β2AR-CHO cell lines

Log EC50 values and percent isoprenaline maximal responses obtained from 3H-cAMP accumulation and CRE-SPAP gene transcription responses in CHO-hβ2 cells. 7-methylcyanopindolol and ICI118551 stimulated inverse agonist concentration responses; thus, IC50 values are given with a comparison with the response in relation to the basal activity, where basal activity = 100%. Values represent mean ± S.E.M. of n separate experiments.

Log EC50/IC50Iso MaximumBasaln
%%
3H-cAMP accumulation
 Cyanopindolol−9.86 ± 0.048.0 ± 0.98
 7-Methylcyanopindolol−9.99 ± 0.1074.5 ± 9.28
 Carazolol−10.14 ± 0.091.3 ± 0.28
 ICI118551−9.48 ± 0.1745.3 ± 3.37
CRE-SPAP production
 Cyanopindolol−9.97 ± 0.0550.8 ± 3.78
 7-MethylcyanopindololNo response8
 Carazolol−10.30 ± 0.136.0 ± 1.44
 ICI 118551No response6
  • ICI118551, (–)-1-[2,3-(dihydro-7-methyl-1H-inden-4-yl)oxy]-3-[(1-methylethyl)-amino]-2-butanol. Iso Max, maximum response compared to the response of isoprenaline.