Cellular oxygen consumption depends on body mass

1995 ◽  
Vol 269 (1) ◽  
pp. R226-R228 ◽  
Author(s):  
R. K. Porter ◽  
M. D. Brand
Keyword(s):  
Oxygen Consumption ◽  
Body Mass ◽  
Metabolic Activity ◽  
Oxygen Consumption Rate ◽  
Consumption Rate ◽  
Fold Increase ◽  
Standard Metabolic Rate ◽  
Tissue Slices ◽  
Rate Of Oxygen Consumption ◽  
Cellular Oxygen

Hepatocytes were isolated from nine species of mammal of different body mass (and standard metabolic rate). The cells were incubated under identical conditions and oxygen consumption measured. The rate of oxygen consumption (per unit mass of cells) scaled with body mass with exponent -0.18. In general, there was a 5.5-fold decrease in oxygen consumption rate with a 12,500-fold increase in body mass. The decrease in oxygen consumption rate was not due to an increase in cell volume with increasing body mass but to a decrease in intrinsic metabolic activity of the cells. This novel finding confirms and explains the decrease in oxygen consumption rate measured in tissue slices from larger mammals by H. A. Krebs (Biochim. Biophys. Acta 4: 249-269, 1950) and recently by P. Couture and A. J. Hulbert [Am. J. Physiol. 268 (Regulatory Integrative Comp. Physiol. 37): R641-R650, 1995].

Cardiovascular changes in the exercising emu

1983 ◽  
Vol 104 (1) ◽  
pp. 193-201 ◽  
Author(s):  
B. Grubb ◽  
D. D. Jorgensen ◽  
M. Conner
Keyword(s):  
Heart Rate ◽  
Cardiac Output ◽  
Oxygen Consumption ◽  
Stroke Volume ◽  
Oxygen Content ◽  
Body Mass ◽  
Fold Increase ◽  
Exercise Heart Rate ◽  
Rate Of Oxygen Consumption ◽  
Cardiovascular Variables

Cardiovascular variables were studied as a function of oxygen consumption in the emu, a large, flightless ratite bird well suited to treadmill exercise. At the highest level of exercise, the birds' rate of oxygen consumption (VO2) was approximately 11.4 times the resting level (4.2 ml kg-1 min-1). Cardiac output was linearly related to VO2, increasing 9.5 ml for each 1 ml increase in oxygen consumption. The increase in cardiac output is similar to that in other birds, but appears to be larger than in mammals. The venous oxygen content dropped during exercise, thus increasing the arteriovenous oxygen content difference. At the highest levels of exercise, heart rate showed a 3.9-fold increase over the resting rate (45.8 beats min-1). The mean resting specific stroke volume was 1.5 ml per kg body mass, which is larger than shown by most mammals. However, birds have larger hearts relative to body mass than do mammals, and stroke volume expressed per gram of heart (0.18 ml g-1) is similar to that for mammals. Stroke volume showed a 1.8-fold increase as a result of exercise in the emus, but a change in heart rate plays a greater role in increasing cardiac output during exercise.

Oxygen consumption by bovine granulosa cells with prediction of oxygen transport in preantral follicles

2013 ◽  
Vol 25 (8) ◽  
pp. 1158 ◽  
Author(s):  
Dongxing Li ◽  
Gabe P. Redding ◽  
John E. Bronlund
Keyword(s):  
Oxygen Consumption ◽  
Granulosa Cells ◽  
Oxygen Transport ◽  
Oxygen Consumption Rate ◽  
Consumption Rate ◽  
Model Parameters ◽  
Preantral Follicles ◽  
Rate Of Oxygen Consumption ◽  
Key Parameter

The rate of oxygen consumption by granulosa cells is a key parameter in mathematical models that describe oxygen transport across ovarian follicles. This work measured the oxygen consumption rate of bovine granulosa cells in vitro to be in the range 2.1–3.3 × 10–16 mol cell–1 s–1 (0.16–0.25 mol m–3 s–1). The implications of the rates for oxygen transport in large bovine preantral follicles were examined using a mathematical model. The results indicate that oocyte oxygenation becomes increasingly constrained as preantral follicles grow, reaching hypoxic levels near the point of antrum formation. Beyond a preantral follicle radius of 134 µm, oxygen cannot reach the oocyte surface at typical values of model parameters. Since reported sizes of large bovine preantral follicles range from 58 to 145 µm in radius, this suggests that oocyte oxygenation is possible in all but the largest preantral follicles, which are on the verge of antrum formation. In preantral bovine follicles, the oxygen consumption rate of granulosa cells and fluid voidage will be the key determinants of oxygen levels across the follicle.

scholarly journals Mutagenesis and Adaptation of the Psychrotrophic Fungus Chrysosporium pannorum A-1 as a Method for Improving β-pinene Bioconversion

Molecules ◽  
2020 ◽  
Vol 25 (11) ◽  
pp. 2589
Author(s):  
Mateusz Kutyła ◽  
Jan Fiedurek ◽  
Anna Gromada ◽  
Krzysztof Jędrzejewski ◽  
Mariusz Trytek
Keyword(s):  
Oxidative Stress ◽  
Oxygen Consumption ◽  
Metabolic Activity ◽  
Oxygen Consumption Rate ◽  
Parental Strain ◽  
Consumption Rate ◽  
Uv Light ◽  
Linear Gradient ◽  
Toxic Substrate ◽  
Substrate Concentrations

Mutagenesis and adaptation of the psychrotrophic fungus Chrysosporium pannorum A-1 to the toxic substrate β-pinene were used to obtain a biocatalyst with increased resistance to this terpene and improved bioconversion properties. Mutants of the parental strain were induced with UV light and N-methyl-N′-nitro-N-nitrosoguanidine. Mutants resistant to β-pinene were isolated using agar plates with a linear gradient of substrate concentrations. Active mutants were selected based on their general metabolic activity (GMA) expressed as oxygen consumption rate. Compared to the parental strain, the most active mutant showed an enhanced biotransformation ability to convert β-pinene to trans-pinocarveol (315 mg per g of dry mycelium), a 4.3-fold greater biocatalytic activity, and a higher resistance to H2O2-induced oxidative stress. Biotransformation using adapted mutants yielded twice as much trans-pinocarveol as the reaction catalyzed by non-adapted mutants. The results indicate that mutagenesis and adaptation of C. pannorum A-1 is an effective method of enhancing β-bioconversion of terpenes.

scholarly journals Oxygen consumption rate in Gasterosteus aculeatus-Schistocephalus solidus system from a non-migratory naturally infected population

2017 ◽  
Author(s):  
Tarallo Andrea ◽  
D’Onofrio Giuseppe ◽  
Agnisola Claudio
Keyword(s):  
Oxygen Consumption ◽  
Oxygen Consumption Rate ◽  
Gasterosteus Aculeatus ◽  
Consumption Rate ◽  
Host Fish ◽  
Schistocephalus Solidus ◽  
Rate Of Oxygen Consumption ◽  
Migratory Population ◽  
Host Parasite ◽  
The Impact

AbstractThe three spine stickleback Gasterosteus aculeatus is a specific obligatory intermediate host for the cestode worm Schistocephalus solidus. This system is commonly used to investigate the host-parasite interaction in fishes. Despite the interesting attempts which have been made to quantify the impact of the parasite over the respiration rate of the host fish, none of the previous reports took in consideration that stickleback is diversified in different ecotypes according to its ability to made reproductive migration, from and to the sea. Here the oxygen consumption rate in specimens of three-spine stickleback collected from a non-migratory population was quantified with the aim to test if the S. solidus infection drives a change in the oxygen consumption level of the host fish. The results showed that the infected fishes have a higher rate of oxygen consumption compared with the uninfected one. The differences were due to a direct effect of the parasite, not merely to its contribution to the whole oxygen consumption rate. The data were compared with previous reports, showing that the non-migratory population was characterized by a different level of oxygen consumption rate. The differences were interpreted in terms of divergence in physiological adaptations which had to be appeared in different populations.

An in situ biofouling monitor for membrane systems

2003 ◽  
Vol 3 (5-6) ◽  
pp. 205-210 ◽  
Author(s):  
J.W.N.M. Kappelhof ◽  
H.S. Vrouwenvelder ◽  
M. Schaap ◽  
J.C. Kruithof ◽  
D. van der Kooij ◽  
...  
Keyword(s):  
Oxygen Consumption ◽  
Oxygen Consumption Rate ◽  
Consumption Rate ◽  
Early Stage ◽  
Membrane Systems ◽  
Active Biomass ◽  
Ongoing Research ◽  
Rate Of Oxygen Consumption ◽  
Non Destructive

Biofouling is a frequently occurring fouling mechanism in membrane applications. Controlling this phenomenon is a challenge due to the difficulty of cleaning biofouling in spiral wound membrane elements. It is assumed that cleaning can be more efficient when biofouling is in an early stage of colonisation. Therefore a sensitive method has to be available for an early identification of biofouling. The present method, the measurement of the normalised pressure drop (NPD) is not specific for biofouling and is not very sensitive. In this research the feasibility of the specific oxygen consumption rate for detection of the activity of biofilms was investigated in membrane systems. The method has the advantages to be specific for active biomass, applicable in situ, non-destructive and more sensitive than NPD. Three experiments demonstrated that the measurement of the rate of oxygen consumption is potentially a simple, reliable method for the measurement of the active biomass in membrane systems. During one of the experiments the method illustrated the effect of cleaning and the regrowth of bacteria afterwards. The method will be further evaluated and standardized. The relation between the specific oxygen consumption rate and the condition of the biofilm, measured by autopsy of membrane elements, will be further explored. The ongoing research will result in an apparatus and procedure, to be used for biofouling identification during the operation of full-scale and pilot plants.

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