The NMDA antagonist MK-801 blocks light effect on melatonin receptor density in rat suprachiasmatic nuclei.
In pinealectomized rats, melatonin receptor density in the suprachiasmatic nuclei was recently shown to be strongly decreased during the dark period. Furthermore, a one-hour long light pulse is able to reverse this dark-induced decrease. We demonstrate here that this effect of a light-pulse during night time is blocked by prior application of the NMDA receptor antagonist MK-801. These results show that the light effect on melatonin receptor density in the SCN is mediated by activation of NMDA-type receptors.
Gauer
F
F
Neurobiologie des Fonctions Rythmiques et Saisonnières', URA-CNRS 1332, Université Louis Pasteur, Strasbourg, France.
Masson-Pévet
M
M
Pévet
P
P
D000818:Animals; D016291:Dizocilpine Maleate / Q000494:pharmacology*; D008027:Light; D008297:Male; D008550:Melatonin / Q000493:pharmacokinetics; D010870:Pineal Gland / Q000502:physiology; D011485:Protein Binding; D051381:Rats; D017208:Rats, Wistar; D011956:Receptors, Cell Surface / Q000187:drug effects* / Q000528:radiation effects*; D044094:Receptors, Melatonin; D013493:Suprachiasmatic Nucleus / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects*
D011956:Receptors, Cell Surface; D044094:Receptors, Melatonin; D016291:Dizocilpine Maleate; D008550:Melatonin