2-[125I]IMLT Binding (COS-7 Cells)a | CHO Cells | Inhibition [3H]Dopamine Release in Rabbit Retinad (pIC50) | ||||||||
---|---|---|---|---|---|---|---|---|---|---|
Stimulation GTPγS Bindingb | Inhibition-Forskolin Stimulated cAMP Accumulationc | |||||||||
hMT1 (pKi) | hMT2(pKi) | Ki Ratio (MT1/MT2) | hMT1 (pEC50) | hMT2 (pEC50) | pEC50 Ratio (MT1/MT2) | hMT1 (pEC50) | hMT2 (pEC50) | pEC50 Ratio (MT1/MT2) | ||
2-Iodomelatonin | 10.2 | 9.7 | 0.3 | 9.7 | 9.8 | 1.1 | 11 | 10.1 | 0.1 | 11.2 |
S 20098 | 9.1 | 10.2 | 14 | 8.8 | 10 | 16 | 9.4 | 10.3 | 7.9 | 12 |
Melatonin | 9.1 | 9.8 | 4.9 | 8.6 | 9.8 | 4.5 | 9.5 | 9.7 | 1.6 | 10.7 |
GR196429 | 8.6e | 9.3e | 4.7e | 8 | 9.0 | 12.6 | 10.5 | |||
6-Chloromelatonin | 7.9 | 9.7 | 57 | 8.3 | 9.3 | 9.6 | 8.1 | 9.8 | 50 | 10.4 |
6-Hydroxymelatonin | 9.4 | 8.3 | 7.3 | 7.2 | 7.4 | 0.6 | 8.7 | |||
5-Methoxyluzindole | 7.5 | 9.6 | 130 | N.D. | N.D. | 1.3 | ||||
8M-PDOT | 7.2 | 8.5 | 20 | N.D. | N.D. | 9.3 | ||||
N-Acetylserotonin | 6.7 | 6.7 | 1.2 | 5.7 | 6.6 | 7.9 | 7.3 | |||
5-MCA-NAT | 5.6 | 6.6 | 10 | N.D. | N.D. | N.D. | ||||
IIK7 | 8.4f | 10.3f | 90 | 8.7f | 10.3f | 44 | N.D. |
IMLT, iodomelatonin; N.D., not determined.
↵a Dubocovich et al. (1997); COS-7 cells transiently transfected.
↵b Audinot et al. (2003).
↵c Browning et al., (2000); CHO cells stably transfected.
↵d Dubocovich (1985, 1995); inhibition of calcium dependent release of dopamine elicited by electrical stimulation.
↵e M. L. Dubocovich, unpublished observations; CHO cells stably transfected.
↵f Faust et al. (2000); NIH 3T3 cells stably transfected.