|
|
||||||||
SLEEP AND TEMPERATURE REGULATION
1Department of Integrative Physiology, School of Human Sciences, Waseda University, Tokorozawa, Saitama; 2Department of Physiology, School of Allied Health Sciences, Faculty of Medicine, Osaka University Suita, Osaka; 3Clock Cell Biology Research Group, National Institute of Advanced Industrial Science and Technology, Institute for Biological Resources and Functions, Tsukuba, Ibaraki; and 4Department of Physiology, School of Sports Sciences, Waseda University, Tokorozawa, Saitama, Japan
Submitted 15 June 2004 ; accepted in final form 20 August 2004
The criptochrome genes (Cry1 and Cry2) are involved in the molecular mechanism that controls the circadian clock, and mice lacking these genes (Cry1//Cry2/) are behaviorally arrhythmic. It has been speculated that the circadian clock modulates the characteristics of thermoregulation, resulting in body temperature (Tb) rhythm. However, there is no direct evidence proving this speculation. We show here that Tb and heat production in Cry1//Cry2/ mice are arrhythmic under constant darkness. In contrast, both rhythms occur under a light-dark cycle and/or periodical food restriction linked with spontaneous activity and/or eating, although they are not robust as those in wild-type mice. The relationship between heat production and Tb in Cry1//Cry2/ mice is linear and identical under any conditions, indicating that their Tb rhythm is determined by heat production rhythm associated with activity and eating. However, Tb in wild-type mice is maintained at a relatively higher level in the active phase than the inactive phase regardless of the heat production level. These results indicate that the thermoregulatory responses are modulated according to the circadian phase, and the Cry genes are involved in this mechanism.
circadian clock; thermoregulation; metabolism
This article has been cited by other articles:
![]() |
J.-D. Li, W.-P. Hu, L. Boehmer, M. Y. Cheng, A. G. Lee, A. Jilek, J. M. Siegel, and Q.-Y. Zhou Attenuated Circadian Rhythms in Mice Lacking the Prokineticin 2 Gene. J. Neurosci., November 8, 2006; 26(45): 11615 - 11623. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Y. Rudaya, A. A. Steiner, J. R. Robbins, A. S. Dragic, and A. A. Romanovsky Thermoregulatory responses to lipopolysaccharide in the mouse: dependence on the dose and ambient temperature Am J Physiol Regulatory Integrative Comp Physiol, November 1, 2005; 289(5): R1244 - R1252. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |