Table 2. IC50 (pM) of insulin and IGF1 to exon 11 point-mutated IR-B midi receptors.
| Receptor |
Insulin IC50 (pM) Geometric mean (95% confidence intervals) |
IGF1 IC50 (pM) Geometric mean (95% confidence intervals) |
|---|---|---|
| WT IR-A | 25.2 (19.8 to 32.0) | 3621 (3024 to 4334) |
| WT IR-B | 32.0 (25.8 to 40.0) | 38053 (30252 to 47865) |
| IR-B K718A | 34.2 (24.0 to 48.6) | 16735 (14882 to 18821)* |
| IR-BT719A | 29.8 (20.4 to 43.6) | 33478 (22708 to 49325) |
| IR-B S720A | 33.5 (26.4 to 42.7) | 34962 (21133 to 57842) |
| IR-B S721A | 30.4 (24.9 to 37.0) | 33600 (32195 to 35067) |
| IR-B G722A | 28.9 (19.4 to 43.1) | 33534 (19647 to 57236) |
| IR-B T723A | 22.9 (15.6 to 33.9) | 30352 (23198 to 39712) |
| IR-B G724A | 24.8 (16.4 to 37.3) | 41652 (24094 to 72004) |
| IR-B E726A | 20.5 (15.5 to 27.2) | 43732 (24770 to 77210) |
| IR-B D727A | 15.8 (10.3 to 24.1)* | 43098 (21814 to 85147) |
| IR-B P728A | 22.1 (7.0 to 70.4) | 43685 (32009 to 59623) |
| IR-B R729A | 19.9 (7.1 to 56.1) | 36352 (19775 to 66826) |
The affinities of insulin and IGF1 to IR-A, IR-B and IR-B exon 11 point-mutated midi receptors were determined in SPA binding assay with displacement of 125I-insulin. The geometric mean of IC50 (pM) and the 95% confidence intervals are given for n = 3–4 independent experiments.
*) Significant difference (p < 0.05) determined by ANOVA with Dunnet’s correction test.