Inhibition of forskolin-induced cAMP formation and enhancement of specific [35S]GTPγS binding in membranes of C6 glioma cells stably expressing h 5-HT1B or h 5-HT1D receptors
| Compound | Inhibition of Forskolin-Evoked cAMP Accumulation pD2 (95% CI) | Enhancement of Specific [35S]GTPγS Binding pD2 app. (95% CI) | ||||||
|---|---|---|---|---|---|---|---|---|
| h 5-HT1B | n | h 5-HT1D | n | h 5-HT1B | n | h 5-HT1D | n | |
| F 11356 | 8.91 (0.22) | 14 | 9.57 (0.20) | 9 | 8.74 (0.08) | 20 | 9.08 (0.14) | 14 |
| 5-HT | 7.81 (0.21) | 5 | 8.62 (0.28) | 8 | 7.04 (0.13) | 8 | 7.84 (0.15) | 9 |
| Tryptamine | 7.04 (0.25) | 3 | 7.86 (0.43) | 4 | 6.10 (0.16) | 3 | N.D. | |
| Zolmitriptan | 7.51 (0.22)2-a | 4 | 9.59 (0.17)2-a | 7 | 7.22 (0.08)2-a | 14 | 8.80 (0.11)2-a | 13 |
| Sumatriptan | 7.16 (0.08)2-a | 22 | 8.79 (0.13)2-a | 18 | 6.63 (0.12)2-a | 12 | 7.75 (0.17)2-a | 10 |
| Naratriptan | 7.85 (0.18)2-a | 15 | 9.15 (0.18)2-a | 7 | 7.64 (0.27) | 7 | 8.36 (0.18) | 6 |
| Rizatriptan | 6.94 (0.20)2-a | 5 | 8.52 (0.11)2-a | 5 | 6.63 (0.17)2-a | 7 | 7.79 (0.09)2-a | 7 |
| Dihydroergotamine | 8.57 (0.20)2-a | 3 | 9.10 (0.53)2-a | 8 | 8.69 (0.03)2-a | 32-a | 9.13 (0.14)2-a | 3 |
Inhibition of forskolin (100 μM)-induced cAMP accumulation and enhancement of specific [35S]GTPγS binding was determined as described in the text. pD2 values correspond to the negative logarithm of the geometric drug concentration that produces 50% of its maximal response and are expressed with 95% CI. pD2 app. corresponds to apparent pD2 values. n corresponds to the number of independent experiments. N.D., not determined.
↵2-a Data from Pauwels et al. (1997).