activation of ampa receptors in the suprachiasmatic nucleus phase-shifts the mouse circadian clock in vivo and in vitroampa受体的激活视交叉上核相移鼠标生物钟体内和体外.pdfVIP

Activation of AMPA Receptors in the Suprachiasmatic Nucleus Phase-Shifts the Mouse Circadian Clock In Vivo and In Vitro 1. 1. 2 1 1 Yasutaka Mizoro , Yoshiaki Yamaguchi , Rena Kitazawa , Hiroyuki Yamada , Masahiro Matsuo , Jean- 1 1 1,2 Michel Fustin , Masao Doi , Hitoshi Okamura * 1 Department of Systems Biology, Kyoto University Graduate School of Pharmaceutical Sciences, Kyoto, Japan, 2 Division of Molecular Brain Science, Kobe University Graduate School of Medicine, Kobe, Japan Abstract 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 (a-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. Citation: Mizoro Y, Yamaguchi Y, Kitazawa R, Yamada H, Matsuo M, et al. (2010) Acti