<p>Reperfusion Microvascular Ischemia After Prolonged Coronary Occlusion: Implications And Treatment With Local Supersaturated Oxygen Delivery</p>

Heterogeneity of oxygen delivery in normoxic and hypoxic states: a fluorometer study

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1978.235.6.h809 ◽

1978 ◽

Vol 235 (6) ◽

pp. H809-H820 ◽

Cited By ~ 3

Author(s):

B. Chance ◽

C. Barlow ◽

Y. Nakase ◽

H. Takeda ◽

A. Mayevsky ◽

...

Keyword(s):

Oxygen Delivery ◽

Coronary Occlusion ◽

Pyridine Nucleotide ◽

Perfused Heart ◽

Intracellular Space ◽

Redox States ◽

Data Points ◽

On Line ◽

Flying Spot

An on-line, real-time histogram display of heterogeneity of oxygen delivery to perfused and in situ organs is afforded by a flying-spot fluorometer that provides excitation for either oxidized flavoprotein of the mitochondrial space or reduced pyridine nucleotide of mitochondrial and cytosolic spaces. Emission from the two fluorochromes is acquired at 10(4) to 10(5) data points/s and histograms of the fluorescence intensity versus the number of occurrences of that intensity are displayed at 1--10 times per second. The histograms show alterations of the intensity and of the degree of heterogeneity of the redox states of perfused heart with model coronary occlusion, of perfused and in situ rat liver, and of rat and gerbil models of stroke. The percentage change of oxygen delivery to the intracellular space can be calculated from the areas under the histogram.

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The biochemistry of drugs and doping methods used to enhance aerobic sport performance

Essays in Biochemistry ◽

10.1042/bse0440063 ◽

2008 ◽

Vol 44 ◽

pp. 63-84 ◽

Cited By ~ 7

Author(s):

Chris E. Cooper

Keyword(s):

Oxygen Uptake ◽

Oxygen Content ◽

Oxygen Delivery ◽

Sport Performance ◽

Blood Substitutes ◽

Altitude Training ◽

Blood Oxygen ◽

Oxygen Carriers ◽

Sports Performance ◽

Blood Doping

Optimum performance in aerobic sports performance requires an efficient delivery to, and consumption of, oxygen by the exercising muscle. It is probable that maximal oxygen uptake in the athlete is multifactorial, being shared between cardiac output, blood oxygen content, muscle blood flow, oxygen diffusion from the blood to the cell and mitochondrial content. Of these, raising the blood oxygen content by raising the haematocrit is the simplest acute method to increase oxygen delivery and improve sport performance. Legal means of raising haematocrit include altitude training and hypoxic tents. Illegal means include blood doping and the administration of EPO (erythropoietin). The ability to make EPO by genetic means has resulted in an increase in its availability and use, although it is probable that recent testing methods may have had some impact. Less widely used illegal methods include the use of artificial blood oxygen carriers (the so-called ‘blood substitutes’). In principle these molecules could enhance aerobic sports performance; however, they would be readily detectable in urine and blood tests. An alternative to increasing the blood oxygen content is to increase the amount of oxygen that haemoglobin can deliver. It is possible to do this by using compounds that right-shift the haemoglobin dissociation curve (e.g. RSR13). There is a compromise between improving oxygen delivery at the muscle and losing oxygen uptake at the lung and it is unclear whether these reagents would enhance the performance of elite athletes. However, given the proven success of blood doping and EPO, attempts to manipulate these pathways are likely to lead to an ongoing battle between the athlete and the drug testers.

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