THE IRRIGATION OF THE GILLS IN FISHES: II. EFFICIENCY OF OXYGEN UPTAKE IN RELATION TO RESPIRATORY FLOW ACTIVITY AND CONCENTRATIONS OF OXYGEN AND CARBON DIOXIDE

1962 ◽  
Vol 40 (5) ◽  
pp. 817-862 ◽  
Author(s):  
Richard L. Saunders
Keyword(s):  
Carbon Dioxide ◽  
Oxygen Consumption ◽  
Oxygen Uptake ◽  
Gill Filament ◽  
Saturated Water ◽  
Respiratory Flow ◽  
Ambient Oxygen ◽  
Low Levels ◽  
Flow Activity ◽  
Ambient Levels

Respiratory volumes, percentage utilizations of oxygen, and rates of oxygen consumption were measured in non-swimming and swimming white suckers, brown bullheads, and carp under various ambient levels of oxygen and carbon dioxide. Up to 85% of the oxygen in the inspired water is removed by quietly breathing fish. Generally, high respiratory volumes are associated with low percentage utilizations of oxygen and vice versa. At high respiratory volumes carp remove about twice as much oxygen from the inspired water as do suckers and bullheads. Respiratory volumes are increased by as much as 30 times over the volume for quiet respiration by low levels of oxygen or high levels of carbon dioxide. Respiratory volumes of swimming fish are greater than those of non-swimming, rested fish in air-saturated water but they are not as high as those of non-swimming fish exposed to low ambient oxygen levels.The effects of moderate increases in ambient carbon dioxide on non-swimming fish may be temporary only. If the rise in the pCO2 is slight to moderate, the percentage utilizations of oxygen at given respiratory volumes are at first depressed but may return, after 3 to 5 hours, to the levels they held before the pCO2 was raised. Actively swimming fish respond to any increase in the pCO2 by permanently increased breathing rates and decreased percentage utilizations of oxygen and rates of oxygen consumption.The number of respiratory units or lamellae per millimeter of gill filament in suckers, bullheads, and carp weighing 200 g are about 14, 10, and 20 respectively, but the total numbers and areas of lamellae are such that total gill areas are nearly identical among these three species.

scholarly journals Effects of Bicarbonate on the Respiration and Glycolytic Activity of Boar Spermatozoa

1978 ◽  
Vol 31 (4) ◽  
pp. 385 ◽  
Author(s):  
RN Murdoch ◽  
WD Davis
Keyword(s):  
Carbon Dioxide ◽  
Energy Source ◽  
Oxygen Consumption ◽  
Apparent Effect ◽  
Glycolytic Activity ◽  
Low Levels ◽  
Presence And Absence ◽  
Boar Spermatozoa

The metabolism of washed boar spermatozoa was studied in the presence and absence of low levels of bicarbonate (6 mM) and carbon dioxide (2 %). Bicarbonate stimulated the oxygen consumption of the spermatozoa but had no apparent effect on glycolysis. The stimulatory effect of bicarbonate on respiration depended on the presence of a utilizable exogenous energy source such as glucose, fructose, lactate, or pyruvate and no stimulation occurred when no substrate was added or when acetate was used as substrate. The response of the spermatozoa to bicarbonate also depended on the presence of adequate concentrations of potassium (5 mM) and to a lesser extent magnesium (1 mM).

Gas Exchange with Air and Water in an Air-Breathing Catfish, Saccobranchus (≡Heteropneustes) Fossilis

1971 ◽  
Vol 55 (3) ◽  
pp. 667-682
Author(s):  
G. M. HUGHES ◽  
B. N. SINGH
Keyword(s):  
Carbon Dioxide ◽  
Oxygen Consumption ◽  
Gas Exchange ◽  
Tap Water ◽  
Free Access ◽  
Experimental Conditions ◽  
Tropical Asia ◽  
Saturated Water ◽  
Oxygenated Water ◽  
Hypoxic Water

1. Gas exchange of Saccobranchus fossilis with water and air has been studied under various experimental conditions which were designed to simulate some of the conditions of tropical Asia. 2. In tap water the fish exchanges gases with both water and air. When kept in air-saturated water it can exchange gases with water alone for periods of 6-12 h or even more. In de-oxygenated water, with free access to air, it obtains oxygen from the air and can live for several days under these conditions. 3. In air-saturated water more oxygen is obtained from water (60%) than from air (40%), but in hypoxic water this ratio is reversed. 4. When the fish is submerged in water, free access to air being prevented, the oxygen consumption is reduced, even in air-saturated water. In hypoxic and hypercarbic water oxygen consumption is further reduced. In air-saturated water about 17% of the oxygen enters via the skin and the rest via the gills. When exchanging gases with water alone and subjected to a gradual hypoxia, the fish shows a less dependent respirator. 5. When the fish is removed from the water its oxygen consumption is reduced. A greater reduction occurs when the fish is kept in de-oxygenated water but allowed to breathe air. 6. When the fish is exchanging gases with both water and air very little carbon dioxide is released into the air (RQ = 0·17). The total RQ in fish removed from the water is low, i.e. 0·58. The fish can survive in hypercarbic water only, provided that the content of carbon dioxide does not exceed 14·5 volumes %, when surfacing becomes necessary.

scholarly journals STUDIES ON THE INTERACTION BETWEEN PHAGOCYTES AND TUBERCLE BACILLI

1956 ◽  
Vol 104 (1) ◽  
pp. 137-150 ◽  
Author(s):  
Hartmann Stähelin ◽  
Manfred L. Karnovsky ◽  
Emanuel Suter
Keyword(s):  
Carbon Dioxide ◽  
Bacillus Subtilis ◽  
Oxygen Consumption ◽  
Oxygen Uptake ◽  
Guinea Pigs ◽  
Significant Degree ◽  
The Other ◽  
Polymorphonuclear Leucocytes ◽  
Mycobacterium Phlei

Tubercle bacilli labelled with C14 were prepared by growth on radioactive substrates such as glycerol, CO2, and acetate. These organisms were exposed in vitro to leucocytes (mostly polymorphonuclear leucocytes) from peritoneal exudates of guinea pigs. The respiration of the leucocytes and of the bacilli, alone and together, was followed by determining oxygen uptake and C14O2 production. When heat-killed labelled tubercle bacilli were exposed to leucocytes there was little or no degradation of bacillary material to C14O2 by leucocytic enzymes. On the other hand, conversion of components of sonically disrupted bacilli to C14O2 by leucocytes was significant. It was possible to determine the oxygen uptake and C14O2 production of phagocytized living tubercle bacilli, and it was found that after phagocytosis the bacilli maintained their rates of oxygen consumption and C14O2 production. This finding was in contrast to observations made with Mycobacterium phlei, a saprophytic acid-fast organism, and with Bacillus subtilis. In these cases oxygen consumption and C14O2 production declined after phagocytosis, and bacterial components were converted to carbon dioxide to a significant degree by leucocytic enzymes.

scholarly journals PO-136 Cycling Incremental test using Breath-by-breath Metabolic Cart to Predict VO2 max

2018 ◽  
Vol 1 (4) ◽  
Author(s):  
Fei Wang ◽  
Haixia Fu
Keyword(s):  
Carbon Dioxide ◽  
Heart Rate ◽  
Oxygen Consumption ◽  
Oxygen Uptake ◽  
Functional Data ◽  
Maximum Oxygen Consumption ◽  
Maximum Heart Rate ◽  
Vo2 Max ◽  
Incremental Test ◽  
Metabolic Cart

Objective Maximal oxygen uptake (VO2 max) is a key indicator to assess health as well as sports performance. In heterogeneous, athletic populations, VO2 max is one of the most frequently measured variables in exercise physiology laboratories. The purpose of this study was to investigate the relationship between Maximal oxygen uptake with other metabolism parameters during one high-intensity activity, and provide simple solution for VO2 max prediction. Methods A total of 27 young athletes were selected. The incremental test was performed on a cycle ergometer (Monark 874 E, Sweden). Participants warmed up for 5 min at 50 watts (W); thereafter, the power output was increased 125 W every 3 min until exhaustion, which was defined as the incapacity to maintain a pedal cadence above 60 revolution per minute (rpm). Oxygen uptake (V̇O2), carbon dioxide production (V̇CO2) and other metabolism indexes were obtained breath-by-breath throughout the test using a metabolic cart (Quark b2, COSMED, Italy). Heart rate (HR) was measured throughout the test using a HR monitor (Polar Vantage NV, Finland). The main method in the VO2 prediction is the use of a mixed effects regression model. The potential explanatory variables include VO2kg (functional data with information on oxygen consumption per kg weight during the test), HR (functional data with heart rate information during the test), MHR (maximum heart rate of the athlete), VO2kgmean (average oxygen consumption during the test), VO2kgmax (maximum oxygen consumption value during the test), VCO2 (carbon dioxide emissions per minute during the test), HRmean (heart rate average), HRmax (maximum heart rate value during the test), age, height, weight. The model statistical analyses were implemented in R platform (version 3.3.3). Results (1) regression model results revealed MHR did not have stronger effects on VO2 max prediction. (2) Parameters of VO2kg, HR, HRmean, height, weight showed relative higher r2 values and lower RMSE values indicating the possible indexes for VO2 max prediction. (3) the interaction effects occurred between indicators which increase the complexity of the model. Conclusions In this study, a simple methodology for the prediction of maximum oxygen consumption has been presented. It combines a relatively simple level of base metabolism parameters. Despite the easy test and low level of exercise required the test provides an rational prediction of VO2 max, which could provide necessary information when it applied as a simple way. 

scholarly journals Control of metabolic gases in hyperbaric chambers

2019 ◽  
Vol XXII (2) ◽  
pp. 61-68
Author(s):  
Stanciu T.
Keyword(s):  
Carbon Dioxide ◽  
Oxygen Consumption ◽  
Carbon Dioxide Production ◽  
Respiratory Effort ◽  
Respiratory Flow ◽  
Hyperbaric Conditions

Respiratory effort in hyperbaric conditions is increased, leading to an increase in the diver's respiratory flow, increased oxygen consumption, and consistent carbon dioxide production. The knowledge of these physical and physiological phenomena involved during the hyperbaric respiration was studied theoretically in collaboration with the "Ovidius" University of Constanta, Faculty of Medicine. They were verified by experimental determinations on groups of divers in the Diving Center hyperbaric complex.

Microbial efficiency in a meromictic reservoir

2008 ◽  
Vol 37 (2) ◽  
Author(s):  
Grażyna Mazurkiewicz-Boroń ◽  
Teresa Bednarz ◽  
Elżbieta Wilk-Woźniak
Keyword(s):  
Carbon Dioxide ◽  
Oxygen Consumption ◽  
Release Rate ◽  
Oxygen Consumption Rate ◽  
Consumption Rate ◽  
Metabolic Efficiency ◽  
Sulphur Compounds ◽  
Carbon Dioxide Release ◽  
Microbial Efficiency ◽  
Ion Contents

Microbial efficiency in a meromictic reservoirIndices of microbial efficiency (expressed as oxygen consumption and carbon dioxide release) were determined in the water column of the meromictic Piaseczno Reservoir (in an opencast sulphur mine), which is rich in sulphur compounds. Phytoplankton abundances were low in both the mixolimnion (up to 15 m depth) and monimolimnion (below 15 m depth). In summer and winter, carbon dioxide release was 3-fold and 5-fold higher, respectively, in the monimolimnion than in the mixolimnion. Laboratory enrichments of the sulphur substrate of the water resulted in a decrease in oxygen consumption rate of by about 42% in mixolimnion samples, and in the carbon dioxide release rate by about 69% in monimolimnion samples. Water temperature, pH and bivalent ion contents were of major importance in shaping the microbial metabolic efficiency in the mixolimnion, whilst in the monimolimnion these relationships were not evident.

Metabolism during normoxia, hyperoxia, and recovery in newborn rats

1992 ◽  
Vol 70 (3) ◽  
pp. 408-411 ◽  
Author(s):  
Peter B. Frappell ◽  
Andrea Dotta ◽  
Jacopo P. Mortola
Keyword(s):  
Carbon Dioxide ◽  
Oxygen Consumption ◽  
Metabolic Rate ◽  
Carbon Dioxide Production ◽  
Oxygen Availability ◽  
Aerobic Metabolism ◽  
Newborn Rats ◽  
Ambient Temperatures ◽  
Positive Effects

Aerobic metabolism (oxygen consumption, [Formula: see text], and carbon dioxide production, [Formula: see text]) has been measured in newborn rats at 2 days of age during normoxia, 30 min of hyperoxia (100% O2) and an additional 30 min of recovery in normoxia at ambient temperatures of 35 °C (thermoneutrality) or 30 °C. In normoxia, at 30 °C [Formula: see text] was higher than at 35 °C. With hyperoxia, [Formula: see text] increased in all cases, but more so at 30 °C (+20%) than at 35 °C (+9%). Upon return to normoxia, metabolism readily returned to the prehyperoxic value. The results support the concept that the normoxic metabolic rate of the newborn can be limited by the availability of oxygen. At temperatures below thermoneutrality the higher metabolic needs aggravate the limitation in oxygen availability, and the positive effects of hyperoxia on [Formula: see text] are therefore more apparent.Key words: neonatal respiration, oxygen consumption, thermoregulation.

scholarly journals No major thermogenic role for (Na+ + K+)-dependent adenosine triphosphatase apparent in hepatocytes from hyperthyroid rats

1982 ◽  
Vol 202 (3) ◽  
pp. 661-665 ◽  
Author(s):  
D G Clark ◽  
M Brinkman ◽  
O H Filsell ◽  
S J Lewis ◽  
M N Berry
Keyword(s):  
Oxygen Consumption ◽  
Oxygen Uptake ◽  
Atpase Activity ◽  
Heat Production ◽  
Adenosine Triphosphatase ◽  
Heat Output ◽  
Liver Parenchymal ◽  
Dependent Atpase ◽  
Parenchymal Cells ◽  
Isolated Liver

(Na+ + K+)-dependent ATPase activity, heat production and oxygen consumption were increased by 59%, 62% and 75% respectively in hepatocytes from tri-iodothyronine-treated rats. Ouabain at concentrations of 1 and 10 mM decreased oxygen uptake by 2-8% in hepatocytes from euthyroid rats and by 5-15% in hepatocytes from hyperthyroid animals. Heat output was decreased by 4-9% with the glycoside in isolated liver parenchymal cells from the control animals and by 11% in the cells from the tri-iodothyronine-treated animals. These results do not support the hypothesis that hepatic (Na+ + K+)-ATPase plays a major role in increased heat production in hepatocytes from hyperthyroid rats.

Sign in / Sign up

Export Citation Format

Share Document