Format

Send to

Choose Destination
See comment in PubMed Commons below
Mech Ageing Dev. 2011 May;132(5):220-9. doi: 10.1016/j.mad.2011.04.001. Epub 2011 Apr 12.

Long-term caloric restriction reduces metabolic rate and heart rate under cool and thermoneutral conditions in FBNF1 rats.

Author information

1
Department of Biomedical Sciences and Program in Neuroscience, Florida State University, College of Medicine, Tallahassee, FL 32306-4340, USA.

Abstract

The long-term metabolic and cardiovascular responses to caloric restriction (CR) are poorly understood. We examined the responses to one year of CR in FBNF1 rats housed in cool (COOL; T(a)=15 °C) or thermoneutral (TMN; T(a)=30 °C) conditions. Rats were acclimated to COOL or TMN for 2 months, instrumented for cardiovascular telemetry and studied in calorimeters. Baseline caloric intake, oxygen consumption (VO(2)), mean arterial blood pressure (MAP), and heart rate (HR) were determined prior to assignment to ad lib (AL) or CR groups (30-40% CR) within each T(a) (n = 8). Groups of rats were studied after 10 weeks CR, one year CR, and after 4 days of re-feeding. Both 10 weeks and one year of CR reduced HR and VO(2) irrespective of T(a). Evaluation of the relationship between metabolic organ mass (liver, heart, brain, and kidney mass) and energy expenditure revealed a clear shift induced by CR to reduce expenditure per unit metabolic mass in both COOL and TMN groups. Re-feeding resulted in prompt elevations of HR and VO(2) to levels observed in control rats. These findings are consistent with the hypothesis that long term CR produces sustained reductions in metabolic rate and heart rate in rats.

PMID:
21513729
PMCID:
PMC3118456
DOI:
10.1016/j.mad.2011.04.001
[Indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science Icon for PubMed Central
    Loading ...
    Support Center