Table 2. Comparison of the radiotracers for WAY-100635 derivatives.
| Radiotracer | Binding affinity a (IC50, nM) | Binding potential | ||||
|---|---|---|---|---|---|---|
| Frontal | Temporal | Insula | Cingulate | Hippocampus | ||
| 11C-WAY-100635 b | - | 3.23 | 4.75 | 5.45 | 4.2 | 4.24 |
| 18F-MPPF c | 3.66 | 0.61 | 0.85 | 0.96 | 0.75 | 1.43 |
| 18F-FCWAY | 2.16 | 2.27 | 2.93 | 3.32 | 2.16 | 3.60 |
| 18F-Mefway | 1.49 | 1.11 | 1.50 | 1.75 | 1.09 | 2.07 |
aIC50 measured in human recombinant 5-HT1A receptors expressed in Chinese hamster ovary cells by using 3H-WAY-100635 [28].
b, c Binding potential values for 11C-WAY-100635 and 18F-MPPF are calculated differently [37], [38].
For 18F-FCWAY and 18F-Mefway, binding potential values were calculated as DVR—1. DVR was a mean value in the various brain regions (this work).