The involvement of calmodulin and Ca2+/calmodulin-dependent protein kinase II in the circadian rhythms controlled by the suprachiasmatic nucleus.
We investigated the involvement of calmodulin and Ca2+/calmodulin-dependent protein kinase II (CaMKII) in the photic entrainment of circadian rhythms using calmodulin inhibitors such as calmidazolium (CMZ) and trifluoperazine (TFP), and a CaMKII inhibitor, KN-62, in rats. Fos expression in the suprachiasmatic nucleus (SCN) of rats induced by photic stimulation (300 lux, 1 h) during the early subjective night of the rats was inhibited by treatment with CMZ (10 mg/kg i.p.) or TFP (20 mg/kg i.p.) 30 min before photic stimulation. With respect to the neuronal firing rate in the rat SCN slice, KN-62 and CMZ application during the early subjective night attenuated the glutamate (10 microM)-induced phase shift. The present results suggest that calmodulin and CaMKII are involved in the photic entrainment mechanism in the rodent SCN.
Fukushima
T
T
Department of Pharmacology, Faculty of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan.
Shimazoe
T
T
Shibata
S
S
Watanabe
A
A
Ono
M
M
Hamada
T
T
Watanabe
S
S
D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine / Q000031:analogs & derivatives / Q000494:pharmacology; D000704:Analysis of Variance; D000818:Animals; D015415:Biomarkers; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000037:antagonists & inhibitors / Q000502:physiology*; D002147:Calmodulin / Q000037:antagonists & inhibitors / Q000502:physiology*; D002940:Circadian Rhythm / Q000502:physiology*; D004353:Drug Evaluation, Preclinical; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D007093:Imidazoles / Q000494:pharmacology; D066298:In Vitro Techniques; D009419:Nerve Tissue Proteins / Q000032:analysis; D016760:Proto-Oncogene Proteins c-fos / Q000032:analysis; D051381:Rats; D017208:Rats, Wistar; D013493:Suprachiasmatic Nucleus / Q000201:enzymology / Q000502:physiology*; D014268:Trifluoperazine / Q000494:pharmacology
D015415:Biomarkers; D002147:Calmodulin; D004791:Enzyme Inhibitors; D007093:Imidazoles; D009419:Nerve Tissue Proteins; D016760:Proto-Oncogene Proteins c-fos; D014268:Trifluoperazine; C031938:calmidazolium; C063302:KN 62; D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D017871:Calcium-Calmodulin-Dependent Protein Kinases