Clock変異マウスの心拍数サーカディアンリズム

IR (HANDLE) Open Access

Bibliographic Information

Other Title
  • Circadian rhythm of heart rate in Clock mutant mouse

Search this article

Description

CLOCK is a positive factor for driving core feedback loop of the Clock genes, and its mutation is known to exhibit abnormal circadian rhythm of locomotor activity. In the present study, we measured a circadian variability of heart rate in Clock mutant mice. Heart rate was recorded continuously from Clock mutant mice using telemetry system, and the rhythmicity and diurnal variation of heart rate were compared to that of body temperature and locomotor activity. Circadian rhythm of heart rate in Clock mutant mice was entrained to 12hr light : 12hr dark (LD) conditions, but under constant light or constant dark conditions the free-running period was severely extended. In the LD conditions, heart rate of wild-type mice began to increase just before the transitional time from light to dark, whereas the increase of heart rate of Clock mutant was delayed for 2hr. This delay was also observed in body temperature and locomotor activity. Cross-correlation between parameters demonstrated that phase of body temperature was about 10 min delayed from that of heart rate. A variability of the heart rate decreased in the Clock mutant in comparison to the wild type. The frequency analysis of the heart rate has demonstrated that the power in Clock mutant was lower in both low frequency and high frequency than that in wild type. These findings suggest that the autonomic nervous activity is suppressed in Clock mutant mice.

Journal

Keywords

Details 詳細情報について

Report a problem

Back to top