| Autor: |
Conway, Shaun, Drew, Janice E, Canning, Sarah J, Barrett, Perry, Jockers, Ralf, Strosberg, A.Donny, Guardiola-Lemaitre, Beatrice, Delagrange, Phillipe, Morgan, Peter J |
| Zdroj: |
FEBS Letters; April 1997, Vol. 407 Issue: 1 p121-126, 6p |
| Abstrakt: |
Binding assays using 2‐[125I]iodomelatonin revealed high‐affinity, guanosine 5′‐O‐(3‐thiotriphosphate) sensitive, melatonin binding sites (Bmax1.1 fmol/mg protein) in the human embryonic kidney cell line HEK293. Competition studies using the selective melatonin receptor antagonist luzindole and RT‐PCR techniques identified these sites as human Mel1amelatonin receptors. Challenge of HEK293 cells with 1 μM melatonin had no effect on forskolin stimulated cyclic AMP levels, whereas in HEK293 cells engineered to stably over‐express the human Mel1amelatonin receptor (Bmax>400 fmol/mg protein) melatonin dose‐dependently inhibited stimulated cyclic AMP levels (IC507.7 pM). These data may indicate that certain tissues, expressing low levels of G protein‐coupled melatonin receptors, do not display melatonin mediated inhibition of cAMP. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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