title: Lowered entrainment function in the suprachiasmatic nucleus of Otsuka Long Evans Tokushima Fatty (OLETF) rats.
abstract: The entrainment function in the suprachiasmatic nucleus (SCN) of young non-diabetic Otsuka Long Evans Tokushima Fatty (OLETF) rats was studied. OLETF rats significantly needed more days for re-entrainment to a new light-dark cycle than control Long Evans Tokushima Otsuka (LETO) rats. We also assessed Fos expression in the SCN induced by dim light exposure. The number of Fos-immunoreactive cells was significantly decreased in 5- to 13-week-old OLETF rats compared with LETO rats. Moreover, the effect of glutamate on neuronal activity in the SCN of OLETF rats were investigated. In young non-diabetic OLETF rats, the phase delay in the SCN neuronal firing rhythm induced by 1 microM glutamate was significantly less than that in LETO rats. These results suggested that the entrainment function is reduced in OLETF rats before the onset of diabetes.
authors.affiliation: Department of Pharmacology, Faculty of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Shimazoe
authors.forename: M
authors.initials: M
authors.lastname: Maetani
authors.forename: S
authors.initials: S
authors.lastname: Nakamura
authors.forename: S
authors.initials: S
authors.lastname: Yamanouchi
authors.forename: S
authors.initials: S
authors.lastname: Watanabe
authors.forename: K
authors.initials: K
authors.lastname: Miyasaka
authors.forename: A
authors.initials: A
authors.lastname: Kono
authors.forename: A
authors.initials: A
authors.lastname: Funakoshi
mesh_terms: D000818:Animals; D002940:Circadian Rhythm; D016762:Genes, fos / Q000502:physiology; D018698:Glutamic Acid / Q000494:pharmacology; D008297:Male; D009474:Neurons / Q000187:drug effects / Q000502:physiology; D051381:Rats; D020318:Rats, Long-Evans; D013493:Suprachiasmatic Nucleus / Q000502:physiology*
chemical_list: D018698:Glutamic Acid