TABLE 1

Pharmacological parameters of exendin-4 and exendin-4-C16

Mean ± S.E.M. parameter estimates from concentration-response analyses in Fig. 1.

Exendin-4Exendin-4-C16
Binding affinity (HEK293-SNAP-GLP-1R, n = 5)
Log Ki (M)−9.2 ± 0.1−8.8 ± 0.1*
Cyclic AMP (HEK293-SNAP-GLP-1R, n = 5)
Log EC50 (M)−9.7 ± 0.1−9.5 ± 0.1
Emax (% global max)101 ± 298 ± 3
Hill slope2.1 ± 0.31.8 ± 0.3
Mini-Gs recruitment (HEK293T, n = 5)
Log EC50 (M)−8.2 ± 0.1−8.3 ± 0.1
Emax268 ± 23171 ± 14*
β-arrestin-2 recruitment (HEK293T, n = 5)
Log EC50 (M)−7.6 ± 0.1−7.7 ± 0.1
Emax (AUC)66 ± 1625 ± 5*
Insulin secretion (INS-1 832/3, n = 6)
Log EC50 (M)−11.0 ± 0.2−10.6 ± 0.1*
Emax1.7 ± 0.12.2 ± 0.2*
  • *P < 0.05 by paired t test.