On the Rate of Oxygen Consumption by Tissues and Lower Organisms as a Function of Oxygen Tension

1933 ◽  
Vol 8 (3) ◽  
pp. 260-274 ◽  
Author(s):  
Pei-Sung Tang
1963 ◽  
Vol 205 (2) ◽  
pp. 325-330 ◽  
Author(s):  
S. Cassin

Critical oxygen tensions of newborn, young, and adult mice are presented. At neutral environmental temperature, oxygen consumption of newborn mice is unaffected by reducing the oxygen tension of inspired air to 85 mm Hg. Five-day-old mice, at neutral environmental temperature, tolerate a decrease in ambient oxygen tension to 100 mm Hg without a depression of oxygen consumption. Adult mice behave in a qualitatively similar fashion. When the ambient temperature is lowered below neutral, the mice are unable to maintain a constant oxygen consumption if hypoxia is induced. It appears as though the depression of oxygen consumption during hypoxia is linearly related to the hypothermic increment to metabolism: the greater the extra oxygen consumption, the more readily it is reduced. Although the newborn mouse is unable to combat hypothermia effectively, it does respond to mild hypothermia for short periods by increasing its rate of oxygen consumption. Evidence is presented of a rapid maturation of temperature controlling mechanisms during growth.


1973 ◽  
Vol 59 (1) ◽  
pp. 255-266
Author(s):  
H. J. ATKINSON

1. The rate of oxygen consumption of individual males of Enoplus brevis and E. communis was measured at 15 °C and at each of four oxygen tensions, 135, 75, 35, and 12 Torr, after at least 12 h experience of these conditions. 2. It was clearly demonstrated that the level of oxygen consumption of both species was reduced by each lowering of the imposed oxygen tension. 3. In all cases the oxygen consumption of each species fell with increasing body size. On a unit dry-weight basis the oxygen consumption of E. brevis is greater than that of the larger E. communis, but after allowing for the difference of body size the two species have more or less similar oxygen uptakes at all oxygen tensions. 4. In E. brevis oxygen tension influenced the relationship of body size and metabolism, the slope relating oxygen consumption and body weight becomes steeper with decreasing oxygen tension. This effect was not shown by E. communis. 5. Some general factors influencing the availability of oxygen to nematodes are considered.


1929 ◽  
Vol 13 (1) ◽  
pp. 27-45 ◽  
Author(s):  
Charles S. Shoup

1. The respiration of luminous bacteria has been studied by colorimetric and manometric methods. 2. Limulus oxyhaemocyanin has been used as a colorimetric indicator of oxygen consumption and indicator dyes were used for colorimetric determination of carbon dioxide production. 3. The Thunberg-Winterstein microrespirometer has been used for the measurement of the rate of oxygen consumption by luminous bacteria at different partial pressures of oxygen. 4. The effect of oxygen concentration upon oxygen consumption has been followed from equilibrium with air to low pressures of oxygen. 5. Luminous bacteria consume oxygen and produce carbon dioxide independent of oxygen pressures from equilibrium with air (152 mm.) to approximately 22.80 mm. oxygen or 0.03 atmosphere. 6. Dimming of a suspension of luminous bacteria occurs when oxygen tension is lowered to approximately 2 mm. Hg (0.0026 atmosphere) and when the rate of respiration becomes diminished one-half. 7. Pure nitrogen stops respiratory activity and pure oxygen irreversibly inhibits oxygen consumption. 8. The curve for rate of oxygen consumption with oxygen concentration is similar to curves for adsorption of gasses at catalytic surfaces, and agrees with the Langmuir equation for the expression of the amount of gas adsorbed in unimolecular layer at catalytic surfaces with gas pressure. 9. A constant and maximum rate of oxygen consumption occurs in small cells when oxygen concentration becomes sufficient to entirely saturate the surface of the oxidative catalyst of the cell.


1927 ◽  
Vol 10 (5) ◽  
pp. 767-779 ◽  
Author(s):  
Wallace O. Fenn

1. The resting rate of oxygen consumption of the excised sciatic nerve of the frog is 1.23 c.mm. of oxygen per gm. of nerve per minute. 2. During stimulation with an induction coil with 100 make and 100 break shocks per second there is an excess oxygen consumption amounting on the average to 0.32 c.mm. of oxygen per gm. of nerve per minute of stimulation, or a 26 per cent increase over the resting rate. 3. The magnitude of the excess oxygen consumption in stimulation, in agreement with the all-or-none law, is not markedly influenced by considerable variations in the intensity of stimulation. 4. Increasing the frequency of stimulation from 100 to 200 shocks per second increases the extra oxygen used only 1.12–1.18 times. The same change in frequency of stimulation increases the negative variation 1.15 times and the heat production about 1.25 times (Hill). 5. This parallelism between the excess oxygen and the negative variation argues definitely for some causal connection between the excess oxygen and the nerve impulse itself. 6. Calculation shows that the oxygen tension inside these nerves was not zero.


In a comparison of muscles poisoned with mono-iodo-acetic acid (IAA) in the presence and in the absence of oxygen respectively, Lundsgaard (1930) found:- (1) That the spontaneous breakdown of phosphagen in poisoned resting muscle is much more rapid under anaerobic conditions. (2) That the onset of the characteristic contracture produced by IAA is accompanied always by an increase in the rate of oxygen consumption.


1996 ◽  
Vol 271 (3) ◽  
pp. F717-F722
Author(s):  
G. Bajaj ◽  
M. Baum

Intracellular cystine loading by use of cystine dimethyl ester (CDME) results in a generalized inhibition in proximal tubule transport due, in part, to a decrease in intracellular ATP. The present study examined the importance of phosphate and metabolic substrates in the proximal tubule dysfunction produced by cystine loading. Proximal tubule intracellular phosphorus was 1.8 +/- 0.1 in control tubules and 1.1 +/- 0.1 nmol/mg protein in proximal tubules incubated in vitro with CDME P < 0.001). Infusion of sodium phosphate in rabbits and subsequent incubation of proximal tubules with a high-phosphate medium attenuated the decrease in proximal tubule respiration and prevented the decrease in intracellular ATP with cystine loading. Tricarboxylic acid cycle intermediates have been shown to preserve oxidative metabolism in phosphate-depleted proximal tubules. In proximal tubules incubated with either 1 mM valerate or butyrate, there was a 42 and 34% reduction (both P < 0.05) in the rate of oxygen consumption with cystine loading. However, tubules incubated with 1 mM succinate or citrate had only a 13 and 14% P = NS) reduction in the rate of oxygen consumption, respectively. These data are consistent with a limitation of intracellular phosphate in the pathogenesis of the proximal tubule dysfunction with cystine loading.


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