Activation of AMPA receptors in the suprachiasmatic nucleus phase-shifts the mouse circadian clock in vivo and in vitro.
The glutamatergic neurotransmission in the suprachiasmatic nucleus (SCN) plays a central role in the entrainment of the circadian rhythms to environmental light-dark cycles. Although the glutamatergic effect operating via NMDAR (N-methyl D-aspartate receptor) is well elucidated, much less is known about a role of AMPAR (alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptor) in circadian entrainment. Here we show that, in the mouse SCN, GluR2 and GluR4 AMPAR subtypes are abundantly expressed in the retinorecipient area. In vivo microinjection of AMPA in the SCN during the early subjective night phase-delays the behavioral rhythm. In the organotypic SCN slice culture, AMPA application induces phase-dependent phase-shifts of core-clock gene transcription rhythms. These data demonstrate that activation of AMPAR is capable of phase-shifting the circadian clock both in vivo and in vitro, and are consistent with the hypothesis that activation of AMPA receptors is a critical step in the transmission of photic information to the SCN.
Department of Systems Biology, Kyoto University Graduate School of Pharmaceutical Sciences, Kyoto, Japan.
Yasutaka
Y
Mizoro
Yoshiaki
Y
Yamaguchi
Rena
R
Kitazawa
Hiroyuki
H
Yamada
Masahiro
M
Matsuo
Jean-Michel
JM
Fustin
Masao
M
Doi
Hitoshi
H
Okamura
D000818:Animals; D056926:CLOCK Proteins; D005786:Gene Expression Regulation / Q000187:drug effects; D066298:In Vitro Techniques; D051379:Mice; D018091:Receptors, AMPA / Q000378:metabolism*; D013493:Suprachiasmatic Nucleus / Q000378:metabolism* / Q000502:physiology; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid / Q000494:pharmacology
D018091:Receptors, AMPA; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid; D056926:CLOCK Proteins; C538944:Clock protein, mouse