Diurnal Changes in Metabolic Rate in Pygmy Marmosets: Implications for Sleep, Torpor, and Basal Metabolism in Primates

The basal metabolism studied in 29 young adults on 349 occasions over 2 years in the Arctic was 37.4 (sd α 3.7) kcal/m-2/hr-1, and well within the normal British standards. The variability showed no relationship to season. On polar expeditions, men's physiologically significant exposure to cold is small because of efficient protection by clothing and shelter. Information is needed about precise differences of microclimate in the polar regions and at home. Field work could more profitably be directed to the cognate problem of costs of various activities in the cold rather than basal metabolic rate. Submitted on April 25, 1960

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Factors regulating basal metabolism of the isolated perfused rabbit heart

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1986.250.6.h998 ◽

1986 ◽

Vol 250 (6) ◽

pp. H998-H1007 ◽

Cited By ~ 2

Author(s):

C. L. Gibbs ◽

G. Kotsanas

Keyword(s):

Metabolic Rate ◽

Coronary Flow ◽

Constant Pressure ◽

Rabbit Heart ◽

Basal Metabolism ◽

Papillary Muscles ◽

O2 Consumption ◽

Calcium Depletion ◽

Experimental Conditions ◽

High K

Basal metabolism has been measured in isolated whole hearts from rabbits and compared with myothermic and polarographic measurements on isolated papillary muscles. Hearts were perfused at constant pressure (Langendorff method) using a modified Krebs-Henseleit solution (KH) with glucose as substrate. Higher levels of basal O2 consumption (MVO2) and coronary flow (CF) were observed when arrest was induced by calcium depletion (low Ca; 0.1 mM CaCl2, 10.0 mM KCl) rather than by potassium excess (high K; 30.0 mM KCl). The metabolic rate of high K arrested hearts was close to earlier myothermic estimates (J. Mol. Cell. Cardiol. 16: 953-962, 1984); polarographic values, however, were about twofold higher, and somewhat higher than the value obtained in low Ca arrested hearts. The addition of erythrocytes, albumin, or dextran significantly reduced CF but did not substantially alter basal MVO2. Basal metabolic rate was substrate- and O2 tension-dependent, and under all experimental conditions there was linear relationship between MVO2 and CF. Extrapolations to zero flow showed that the basal MVO2 values so obtained were similar in low Ca or high K and were not altered by the presence of erythrocytes. Our results show that there are several factors regulating basal metabolism.

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Laboratory Metabolism of Incubating Semipalmated Plovers

The Condor ◽

10.1093/condor/108.4.966 ◽

2006 ◽

Vol 108 (4) ◽

pp. 966-970

Author(s):

Mark Williamson ◽

Joseph B. Williams ◽

Erica Nol

Keyword(s):

Critical Temperature ◽

Metabolic Rate ◽

Breeding Season ◽

Basal Metabolic Rate ◽

Low Temperatures ◽

Thermal Conductance ◽

Basal Metabolism ◽

The Arctic ◽

Lower Critical Temperature ◽

Metabolic Data

Abstract Abstract The Semipalmated Plover (Charadriussemipalmatus), anarctic-nesting migratory shorebird, regularlyencounters low temperatures during the breedingseason. We measured the basal metabolism of adultsduring incubation at Churchill, Manitoba, Canada todetermine basal metabolic rate (BMR),lower critical temperature(Tlc), total evaporative waterloss (TEWL), and dry thermal conductance(Cm). BMR and Tlcwere 47.4 kJ day−1and 23.3°C, respectively, TEWL was2.5 mL H2O−d,and Cm was1.13 mW g−1 °C−1.Measured BMR and Tlc were consistentwith high values found for other shorebird speciesbreeding in the Arctic, while Cm was18% higher than predicted from allometricequations. These metabolic data suggest thatSemipalmated Plovers are adapted to balance therequirements of incubation against energetic andthermoregulatory demands in the Arctic, especiallyin harsh early breeding season conditions.

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Basal metabolism and respiration in men living at 5,800 m (19,000 ft)

Journal of Applied Physiology ◽

10.1152/jappl.1964.19.5.949 ◽

1964 ◽

Vol 19 (5) ◽

pp. 949-954 ◽

Cited By ~ 40

Author(s):

M. B. Gill ◽

L. G. C. E. Pugh

Keyword(s):

Metabolic Rate ◽

Basal Metabolic Rate ◽

Basal Respiration ◽

Mean Value ◽

Alveolar Ventilation ◽

Basal Metabolism ◽

South American ◽

Insufficient Evidence ◽

Prolonged Stay ◽

The Mean

Respiratory determinations were carried out on eight members of the Himalayan Scientific and Mountaineering Expedition 1960—1961 and three Sherpas during a prolonged stay at 5,800 m (19,000 ft). Ventilation and oxygen uptake were similar in both groups, although the Sherpas were smaller men. The Sherpas had lower alveolar ventilation, higher PaCOCO2 and lower PaOO2 values than the scientists. Among six of the scientists mean basal metabolic rate was 10% above the mean value predicted from sea-level standards. There was no increase in the two others, who did not acclimatize. The mean basal metabolic rate in the three Sherpas was +21%. The findings were not explained by the extra O2 cost of increased breathing, changes in body composition, or exposure to cold, although this may have been a factor in the Sherpas. The results were similar to recent South American data on residents at 4,540 m (14,900 ft). It was concluded that acclimatization to great altitudes in man is associated with increase in basal metabolism, but there is insufficient evidence as to whether this is a response to hypoxia or other environmental factors. basal respiration; acclimatized men; high altitude (5,800 m) Submitted on March 30, 1964

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Age Changes in Body Size, Body Composition and Basal Metabolism

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1956.186.2.207 ◽

1956 ◽

Vol 186 (2) ◽

pp. 207-210 ◽

Cited By ~ 11

Author(s):

M. C. Conrad ◽

A. T. Miller

Keyword(s):

Body Composition ◽

Body Size ◽

Metabolic Rate ◽

Relative Weight ◽

Extracellular Fluid ◽

The Body ◽

Basal Metabolism ◽

Albino Rats ◽

Tissue Mass ◽

Bone Minerals

The interrelations of body size, body composition and basal metabolism were studied in 69 albino rats ranging in age from 18–174 days. The decline in metabolic rate with age was more rapid than would be predicted from the weight0.75 rule which eliminates the influence of body size in interspecific measurements. Body composition analyses indicated that the increase with age in metabolically inert fat and bone minerals was approximately balanced by a corresponding decrease in metabolically inert extracellular fluid, so that ‘active tissue mass’ was virtually unchanged. Calculations based on data in the literature indicate that about one-half the decline in metabolic rate with age may be due to the corresponding decrease in the relative weight of the viscera. The remainder of the decline in metabolic rate must be due to factors other than changes in the chemical or histological composition of the body.

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The Developmental Efficiency of the Avian Embryo

Journal of Experimental Biology ◽

10.1242/jeb.5.1.43 ◽

1927 ◽

Vol 5 (1) ◽

pp. 43-54

Author(s):

JOSEPH NEEDHAM

Keyword(s):

Growth Rate ◽

Metabolic Rate ◽

Basal Metabolism ◽

Energetic Efficiency ◽

Avian Embryo ◽

Efficiency Coefficient

1. The "Coefficient d'Utilisation" or Plastic Efficiency Coefficient (P.E.C.) has been calculated for each day during development. It has a trough which is deepest between the eighth and ninth days; development is therefore most expensive at this point. The correlation between this and the point of greatest intensity of protein combustion is exact. 2. The "Rendement Energétique brut" or Apparent Energetic Efficiency has been calculated for each day during development. It rises, changing more rapidly towards the end than at the beginning; thus it resembles the metabolic rate rather than the growth rate. The "Rendement Energétique réel" or Real Energetic Efficiency cannot at present be calculated for the basal metabolism of the embryo is unknown and it is not certain whether the usual conceptions of basal metabolism can be applied to a rapidly growing and changing organism.

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THE RELATION OF HEART WEIGHT TO THE BASAL METABOLISM AS VARIED BY THYROID ADMINISTRATION

Journal of Experimental Medicine ◽

10.1084/jem.55.6.903 ◽

1932 ◽

Vol 55 (6) ◽

pp. 903-909 ◽

Cited By ~ 4

Author(s):

Francis M. Smith ◽

Eaton M. MacKay

Keyword(s):

Metabolic Rate ◽

Linear Relationship ◽

Basal Metabolic Rate ◽

Basal Metabolism ◽

Heart Weight ◽

Albino Rat ◽

Hypertrophy Of The Myocardium

A linear relationship exists in the albino rat between the heart weight and the basal metabolic rate when varied by the administration of active thyroid material. It is suggested that this increase in heart weight which follows the increase in metabolism after thyroid is in the nature of a simple work hypertrophy of the myocardium.

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BASAL METABOLIC RATE IN OBESE CHILDREN

PEDIATRICS ◽

10.1542/peds.4.6.744 ◽

1949 ◽

Vol 4 (6) ◽

pp. 744-750

Author(s):

ALBERTA ILIFF ◽

HARRY H. GORDON ◽

HELEN MCNAMARA ◽

W. RANDAL BELL

Keyword(s):

Metabolic Rate ◽

Surface Area ◽

Basal Metabolic Rate ◽

Research Council ◽

Basal Metabolism ◽

Metabolic Rates ◽

Obese Children ◽

Child Research

An analysis of the results of 524 observations of the basal metabolism of 348 obese children is presented. Since only 3% of the basal metabolic rates were lower than minus 15% of the Child Research Council surface area-age standards, it is suggested that these standards can be used satisfactorily in the management of children with obesity. For reasons which are not obvious these standards do not suffice for children with dwarfism.

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