Oxygen consumption of desert pupfish at ecologically relevant temperatures suggests a significant role for anaerobic metabolism

2018 ◽  
Vol 188 (5) ◽  
pp. 821-830 ◽  
Author(s):  
Matt Heuton ◽  
Luis Ayala ◽  
Aldo Morante ◽  
Kyle Dayton ◽  
Alexander C. Jones ◽  
...  
Keyword(s):  
Oxygen Consumption ◽  
Significant Role ◽  
Anaerobic Metabolism ◽  
Desert Pupfish

Metabolic and Tissue Solute Changes Associated With Changes in the Freezing Tolerance of the Bivalve Mollusc Modiolus Demissus

1977 ◽  
Vol 69 (1) ◽  
pp. 1-12
Author(s):  
DENNIS J. MURPHY
Keyword(s):  
Oxygen Consumption ◽  
Low Temperature ◽  
Freezing Tolerance ◽  
Anaerobic Metabolism ◽  
Arrhenius Plot ◽  
Physiological Mechanism ◽  
Temperature Acclimation ◽  
Anaerobic Conditions ◽  
Rate Of Oxygen Consumption ◽  
Dependent Mechanism

1. A physiological mechanism responsible for increasing the freezing tolerance of the bivalve Modiolus demissus (Dillwyn) following low-temperature acclimation was demonstrated. 2. The rates of oxygen consumption of M. demissus acclimated to temperatures between 0 and 24 °C were presented as an Arrhenius plot. A change in slope occurred at 10 °C, suggesting that temperature alone was not responsible for the increased decline in the rate of oxygen consumption below 10 °C. 3. Low-temperature acclimation had no effect on blood Na+ or K+ concentrations but did reduce the concentration of blood Mg2+ and, in addition, resulted in the accumulation of end-products characteristic of anaerobic metabolism - tissue alanine and proline, and blood Ca2+. Furthermore, maintenance of M. demissus under anaerobic conditions increased freezing tolerance. 4. Taken together, these data indicate that the increased freezing tolerance of M. demissus acclimated to low temperatures involves a conversion to anaerobic metabolism. 5. The increase in blood Ca2+ following low-temperature acclimation was associated with the increased freezing tolerance. Finally, Mg2+ simulated the effect of Ca2+ on freezing tolerance, but was only 20% as effective. 6. These results suggest that a Ca2+-dependent mechanism responsible for increasing the freezing tolerance of M. demissus exists, and that the increase in blood Ca2+ is due to a conversion to anaerobic metabolism.

Myocardial anaerobic metabolism in intact dogs

1963 ◽  
Vol 204 (3) ◽  
pp. 427-432 ◽  
Author(s):  
William A. Neill ◽  
Norman Krasnow ◽  
Herbert J. Levine ◽  
Richard Gorlin
Keyword(s):  
Energy Source ◽  
Oxygen Consumption ◽  
Oxidative Metabolism ◽  
Anaerobic Metabolism ◽  
Muscle Metabolism ◽  
Mechanical Work ◽  
Work Output ◽  
Heart Work ◽  
Anaerobic Energy ◽  
The Difference

Energy liberated from substrates of heart muscle metabolism appears as mechanical work and heat. External mechanical work and heat production of the left ventricle were compared with its oxygen consumption in intact dogs. Under control conditions, within the range of accuracy possible, the sum of work and heat was equal to energy from oxidative metabolism. Intravascular administration of cyanide increased heart work but reduced its rate of aerobic metabolism. During the cyanide effect, work plus heat exceeded the energy available from oxidative metabolism. The difference represents myocardial anaerobic metabolism. Since the energy of mechanical work output alone was greater than the myocardial aerobic energy source, a portion of the anaerobic energy liberated must have been converted to mechanical work.

Splanchnic Oxygen Consumption Is Impaired during Severe Acute Normovolemic Anemia in Anesthetized Humans

2006 ◽  
Vol 105 (1) ◽  
pp. 37-44 ◽  
Author(s):  
Mali Mathru ◽  
Daneshvari R. Solanki ◽  
Lee C. Woodson ◽  
J Sean Funston ◽  
Orthan Ozkan ◽  
...  
Keyword(s):  
Oxygen Consumption ◽  
Oxygen Delivery ◽  
Biochemical Markers ◽  
Anaerobic Metabolism ◽  
Hemoglobin Concentration ◽  
Whole Body ◽  
Before And After ◽  
Normovolemic Anemia ◽  
Splanchnic Oxygen ◽  
Beta Hydroxybutyrate

Background In conscious humans, reduction in hemoglobin concentration to 5 g/dl did not produce inadequate systemic oxygenation. However, systemic measures of inadequate oxygenation may not be sufficiently sensitive to detect inadequate oxygenation in individual organs such as splanchnic organs. The authors tested the hypothesis that acute normovolemic anemia to hemoglobin less than 6.0 g/dl in anesthetized humans reduces splanchnic oxygen consumption because of diminished whole body oxygen delivery. Methods Elective spine (n = 12) and abdominal (n = 7) surgery patients underwent acute normovolemic anemia to decrease the hemoglobin concentration close to 6.0 g/dl. The authors assessed the development of supply-dependent conditions in systemic and regional vascular beds by two primary measures before and after acute normovolemic anemia: oxygen consumption and surrogate biochemical markers of anaerobic metabolism, including plasma lactate, regional lactate kinetics, and ketone body ratio. Results When hemoglobin was reduced from 13.6 +/- 1.2 to 5.9 +/- 0.3 g/dl, oxygen supply dependency occurred in the splanchnic and preportal tissues but not at the systemic level. Regional supply dependency was accompanied by biochemical markers of anaerobic metabolism. Conclusions In anesthetized humans, a reduction in hemoglobin to 5.9 g/dl by acute normovolemic anemia diminished splanchnic and preportal whole body oxygen delivery and impaired splanchnic and preportal oxygen consumption. This was accompanied by increased plasma levels of regional lactate and an increased beta-hydroxybutyrate-to-acetoacetate ratio. These findings suggest that the risk to the gastrointestinal tract during acute normovolemic anemia may be underestimated.

The respiratory metabolism of temperature-adapted flatfish at rest and during swimming activity and the use of anaerobic metabolism at moderate swimming speeds

1982 ◽  
Vol 97 (1) ◽  
pp. 359-373 ◽  
Author(s):  
G. G. Duthie
Keyword(s):  
Oxygen Consumption ◽  
Lactic Acid ◽  
White Muscle ◽  
Anaerobic Metabolism ◽  
Swimming Activity ◽  
Respiratory Metabolism ◽  
Maximum Oxygen Consumption ◽  
Cost Of Locomotion ◽  
The Cost ◽  
The Relationship

(1) The standard oxygen consumption and the oxygen consumption during measured swimming activity have been determined in three flatfish species at 5, 10 and 15 degrees C. (2) The relationship between weight and standard oxygen consumption for flatfish conform to the general relationship Y = aWb. On an interspecies basis, standard oxygen consumption of flatfish is significantly lower than that of roundfish. (3) A semilogarithmic model describes the relationship between oxygen consumption and swimming speed for the three species. Values for maximum oxygen consumption, metabolic scopes and critical swimming speeds are low in comparison to salmonids. (4) The optimum swimming speeds and critical swimming speeds of flatfish are similar. It is suggested that, over long distances, flatfish adopt a strategy of swimming at supercritical speeds with periods of intermittent rest to repay the accrued oxygen debt. (5) Elevated lactic acid levels in flounder white muscle after moderate swimming indicate an additional 15% anaerobic contribution to the cost of locomotion as calculated from aerobic considerations.

scholarly journals CHANGES IN OXYGEN CONSUMPTION (NOT ANAEROBIC METABOLISM) DRIVE OUTCOMES AFTER EXERCISE THERAPY IN CARDIAC REHABILITATION

2020 ◽  
Vol 75 (11) ◽  
pp. 1971
Author(s):  
Sergey Kachur ◽  
Alban DeSchutter ◽  
Carl Lavie ◽  
Andrew Elagizi ◽  
Rikin Kadakia ◽  
...  
Keyword(s):  
Oxygen Consumption ◽  
Cardiac Rehabilitation ◽  
Exercise Therapy ◽  
Anaerobic Metabolism

Fetal intestinal oxygen consumption at various levels of oxygenation

1982 ◽  
Vol 242 (1) ◽  
pp. H50-H54 ◽  
Author(s):  
D. I. Edelstone ◽  
I. R. Holzman
Keyword(s):  
Blood Flow ◽  
Oxygen Consumption ◽  
Intestinal Tract ◽  
Anaerobic Metabolism ◽  
Base Excess ◽  
Oxygen Extraction ◽  
Arterial Blood ◽  
Radioactive Microsphere ◽  
Radioactive Microsphere Technique ◽  
Fick Equation

In seven chronically catheterized fetal lambs, blood flow and oxygen consumption (VO2) in the combined small and large intestines were determined at various oxygen concentrations in fetal arterial blood (CaO2). Intestinal blood flow (Qi) was measured with the radioactive-microsphere technique; intestinal oxygen delivery (DO2 = Qi X CaO2), VO2 [Qi X C(a-v)O2, where oxygen extraction [C(a-v)O2/CaO2] were computed with the Fick equation. Compared with normally oxygenated fetuses (CaO2 greater than 6.6 ml/dl), moderately hypoxemic fetuses (CaO2 = 4.4-6.6 ml/dl) had decreased intestinal DO2, increased oxygen extraction, and no change in intestinal VO2, Qi, or mesenteric-venous pH and base excess. During severe fetal hypoxemia (CaO2 less than 4.4 ml/dl), DO2 decreased further while oxygen extraction increased substantially. Intestinal VO2 dropped, however, because the rise in oxygen extraction could no longer completely compensate for the reduced DO2. With severe hypoxemia, Qi and mesenteric-venous pH and base excess also fell. These data indicate that the fetal intestinal tract is able to meet its oxygen needs during hypoxemia until a critically low level of oxygenation is reached. Below this level intestinal oxygenation becomes inadequate, and anaerobic metabolism ensures.

Oxygen consumption, carbon dioxide production and lactic acid during normothermic cardiopulmonary bypass

Perfusion ◽  
2000 ◽  
Vol 15 (5) ◽  
pp. 441-446 ◽  
Author(s):  
Milo Engoren ◽  
Michael Evans
Keyword(s):  
Oxygen Consumption ◽  
Lactic Acid ◽  
Cardiopulmonary Bypass ◽  
Anaerobic Metabolism ◽  
Tertiary Care ◽  
Carbon Dioxide Production ◽  
Care Community ◽  
Tissue Ischemia ◽  
Measure Oxygen Consumption ◽  
A Prospective Study

The objective of this study was to measure oxygen consumption, carbondioxide production and lactic acid levels during normothermic cardiopulmonary bypass. A prospective study was undertaken in a tertiary care community hospital, involving 20 adults undergoing cardiopulmonary bypass with prolonged (>65 min) crossclamping of the aorta. O2 consumption, CO2 production, hemoglobin and lactic acid levels were measured 5, 35 and 65 min after crossclamping of the aorta. O2 consumption was 79.7 ± 14.5, 78.8 ± 15.4 and 81.5 ± 14.1 ml/min/m2 at 5, 35 and 65 min after crossclamping the aorta. CO2 production was 61.8 ± 42.9, 60.6 ± 26.3 and 62.2 ± 35.9 ml/min/m2 at the same times. Lactic acid levels were 1.6 ± 0.5 mM/dl at all three times and did not correlate with O2 consumption or CO2 production. In conclusion, although oxygen consumption was low, there was no evidence of abnormal lactate or anaerobic metabolism to suggest tissue ischemia.

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