IRA values calculated from the simulated agonist concentration-response curves shown in Fig. 3A
| Agonist | KD | Intrinsic efficacy | Relative activity5-a | EC50 | Emax5-b | Hill coefficient | Relative potency5-c | IRA5-d | CorrectedIRA5-e |
|---|---|---|---|---|---|---|---|---|---|
| μM | ɛ | μM | % | ||||||
| Standard agonist | 1.0 | 10 | 1.0 | 0.0909 | 100 | 1.00 | 1.00 | 1.0 | |
| Agonist A | 1.0 | 5 | 0.5 | 0.167 | 91.6 | 1.00 | 0.544 | 0.5 | 0.5 |
| Agonist B | 1.0 | 2.5 | 0.25 | 0.286 | 78.5 | 1.00 | 0.318 | 0.25 | 0.25 |
| Agonist C | 1.0 | 1.25 | 0.125 | 0.444 | 61.0 | 1.00 | 0.205 | 0.125 | 0.125 |
| Agonist D | 1.0 | 0.6 | 0.06 | 0.625 | 41.3 | 1.00 | 0.145 | 0.060 | 0.060 |
| Agonist E | 1.0 | 0.3 | 0.03 | 0.769 | 25.4 | 1.00 | 0.118 | 0.030 | 0.030 |
| Agonist F | 1.0 | 0.15 | 0.015 | 0.870 | 14.3 | 1.00 | 0.104 | 0.015 | 0.015 |
The simulations were for a noncooperative stimulus-response function (n = 1) with low sensitivity (K = 1.0) (see eq. 3).
↵5-a Relative activity is calculated from the dissociation constant (K D) and intrinsic efficacy (ɛ) using eq.5.
↵5-b The maximal response is expressed relative to that of the standard agonist.
↵5-c Denotes the EC50 value of the standard agonist divided by that of the test agonist.
↵5-d The IRA value was calculated from the EC50 and E max values according to eq.1.
↵5-e The corrected IRA values were calculated according to the method outlined in the .