title: Differential entrainment of peripheral clocks in the rat by glucocorticoid and feeding.
abstract: The suprachiasmatic nucleus is the master circadian clock and resets the peripheral clocks via various pathways. Glucocorticoids and daily feeding are major time cues for entraining most peripheral clocks. However, recent studies have suggested that the dominant timing factor differs among organs and tissues. In our current study, we reveal differences in the entrainment properties of the peripheral clocks in the liver, kidney, and lung through restricted feeding (RF) and antiphasic corticosterone (CORT) injections in adrenalectomized rats. The peripheral clocks in the kidney and lung were found to be entrained by a daily stimulus from CORT administration, irrespective of the meal time. In contrast, the liver clock was observed to be entrained by an RF regimen, even if daily CORT injections were given at antiphase. These results indicate that glucocorticoids are a strong zeitgeber that overcomes other entrainment factors regulating the peripheral oscillators in the kidney and lung and that RF is a dominant mediator of the entrainment ability of the circadian clock in the liver.
authors.affiliation: Department of Anatomy and Neurobiology, Kinki University School of Medicine, 377-2 Ohno-Higashi, Osakasayama City, Osaka 589-8511, Japan. sujino@med.kindai.ac.jp
authors.forename: Mitsugu
authors.initials: M
authors.lastname: Sujino
authors.forename: Keiichi
authors.initials: K
authors.lastname: Furukawa
authors.forename: Satoshi
authors.initials: S
authors.lastname: Koinuma
authors.forename: Atsuko
authors.initials: A
authors.lastname: Fujioka
authors.forename: Mamoru
authors.initials: M
authors.lastname: Nagano
authors.forename: Masayuki
authors.initials: M
authors.lastname: Iigo
authors.forename: Yasufumi
authors.initials: Y
authors.lastname: Shigeyoshi
mesh_terms: D000315:Adrenalectomy; D000818:Animals; D057906:Circadian Clocks / Q000187:drug effects* / Q000502:physiology; D002940:Circadian Rhythm / Q000187:drug effects / Q000502:physiology; D003345:Corticosterone / Q000494:pharmacology*; D005247:Feeding Behavior / Q000502:physiology*; D015870:Gene Expression / Q000187:drug effects; D005938:Glucocorticoids / Q000494:pharmacology*; D007668:Kidney / Q000187:drug effects / Q000378:metabolism; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008168:Lung / Q000187:drug effects / Q000378:metabolism; D008297:Male; D056950:Period Circadian Proteins / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013493:Suprachiasmatic Nucleus / Q000187:drug effects* / Q000502:physiology
chemical_list: D005938:Glucocorticoids; D056950:Period Circadian Proteins; D003345:Corticosterone