Dietary Protein Modulates Circadian Changes in Core Body Temperature and Metabolic Rate in Rats

• Yamaoka Ippei

  Department of Anatomy and Neurobiology, Faculty of Medicine, Kagawa University Division of Pharmacology, Drug Safety and Metabolism, Otsuka Pharmaceutical Factory, Inc.

• Nakayama Mitsuo

  Division of Pharmacology, Drug Safety and Metabolism, Otsuka Pharmaceutical Factory, Inc.

• Miki Takanori

  Department of Anatomy and Neurobiology, Faculty of Medicine, Kagawa University

• Yokoyama Toshifumi

  Department of Anatomy and Neurobiology, Faculty of Medicine, Kagawa University

• Takeuchi Yoshiki

  Department of Anatomy and Neurobiology, Faculty of Medicine, Kagawa University

Abstract

We assessed the contribution of dietary protein to circadian changes in core body temperature (T_b) and metabolic rate in freely moving rats. Daily changes in rat intraperitoneal temperature, locomotor activity (LMA), whole-body oxygen consumption (VO₂), and carbon dioxide production (VCO₂) were measured before and during 4 days of consuming a 20% protein diet (20% P), a protein-free diet (0% P), or a pair-fed 20% P diet (20% P-R). Changes in T_b did not significantly differ between the 20% P and 20% P-R groups throughout the study. The T_b in the 0% P group remained elevated during the dark (D) phase throughout the study, but VO₂, VCO₂, and LMA increased late in the study when compared with the 20% P-R group almost in accordance with elevated T_b. By contrast, during the light (L) phase in the 0% P group, T_b became elevated early in the study and thereafter declined with a tendency to accompany significantly lower VO₂ and VCO₂ when compared with the 20% P group, but not the 20% P-R group. The respiratory quotient (RQ) in the 0% P group declined throughout the D phase and during the early L phase. By contrast, RQ in the 20% P-R group consistently decreased from the late D phase to the end of the L phase. Our findings suggest that dietary protein contributes to the maintenance of daily oscillations in T_b with modulating metabolic rates during the D phase. However, the underlying mechanisms of T_b control during the L phase remain obscure.<br>

Journal

• The Journal of Physiological Sciences

  The Journal of Physiological Sciences 58 (1), 75-81, 2008

  PHYSIOLOGICAL SOCIETY OF JAPAN

Keywords

• thermogenesis
• amino acid
• low protein diet
• behavior
• food ingestion

Details

• CRID: 1390282680228763904
• NII Article ID: 10022597776
• NII Article ID: 130004466917
• NII Book ID: AA12129145
• DOI: 10.2170/physiolsci.rp006707
• ISSN: 18806562
• ISSN: 18806546
• NDL BIB ID: 9399778
• PubMed: 18237456
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I9399778
• Web Site: https://search.jamas.or.jp/link/ui/2008203857
• Text Lang: en
• Data Source:
  • JaLC
  • NDL
  • Crossref
  • PubMed
  • CiNii Articles
• Abstract License Flag: Disallowed