Table 4.
Effect of forskolin on basal, Emax and pEC50 values of 5-HT-induced cAMP formation in transiently transfected COS-7 cells with either human wild-type or S267K mutant 5-HT6 receptor
| cAMP formation | ||||||
|---|---|---|---|---|---|---|
| 5-HT6 receptor | Wild-type | S267K | ||||
| Basal (pmol 106 cells−1) | 5-HT Emax (pmol 106 cells−1) | pEC50 | Basal (pmol 106 cells−1) | 5-HT Emax (pmol 106 cells−1) | pEC50 | |
| w/o Forskolin | 7.8±0.3 | 19.5±0.8 | 8.21±0.13 | 10.4±0.5a | 18.1±0.2 | 8.60±0.07 |
| 1 μM Forskolin | 11.6±0.4b | 23.1±1.5 | 8.25±0.17 | 18.8±0.7c | 23.6±0.4d | 8.86±0.04e |
| 3 μM Forskolin | 16.1±0.9 | 26.6±0.9f | 8.21±0.10 | 21.5±2.2 | 24.9±0.1 | 8.62±0.04 |
| 10 μM Forskolin | 20.9±0.9 | 27.9±0.7 | 8.57±0.11 | 24.4±2.0 | 27.1±0.6 | 8.58±0.17 |
Emax and pEC50 values were derived from cAMP-mediated 5-HT response curves as illustrated in Figure 8. Data correspond to mean±s.e.m. values of four to eight independent experiments performed in duplicate. a: P<0.05 versus basal value wild-type 5-HT6 receptor; b: P<0.001 versus basal w/o forskolin wild type 5-HT6 receptor; c: P<0.01 versus basal value w/o forskolin mutant 5-HT6 receptor; d: P<0.001 versus Emax 5-HT w/o forskolin mutant 5-HT6 receptor; e: P<0.01 versus pEC50 wild-type 5-HT6 receptor; f: P<0.01 versus Emax 5-HT w/o forskolin wild type 5-HT6 receptor.