PubMed · 13448527
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
G D'ANTUONO. 1957. [Thrombocythemia].. https://pubmed.ncbi.nlm.nih.gov/13448527/
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Both polycythemia and the increase in hypoxic ventilatory response (HVR) are considered as important factors of acclimatization to hypoxia. The objective of this study was to characterise the ventilation pattern at different inspired oxygen fraction in a model of chronic anemic mice. These mice have a targeted disruption in the 5' untranslated region of the Epo gene that reduces Epo expression such that the homozygous animal is severely anemic. Ventilation in normoxia in Epo-TAg(h) mice was significantly greater than in wild type, and the difference was mainly due to a higher tidal volume. HVR was higher in Epo-TAg(h) mice at every FIO2 suggesting a higher chemosensitivity. Resting oxygen consumption was maintained in anemic mice. Maximal oxygen consumption was 30% lower while hemoglobin was 60% lower in anemic mice compared to wild type. This small decrease in maximal oxygen consumption is probably due a greater cardiac output and/or a better tissue oxygen extraction and would allow these anemic mice to acclimatize to hypoxia in spite of low oxygen carrying capacity. In conclusion, Epo-TAg(h) anemic mice showed increased ventilation and hypoxic ventilatory response. However, whether these adaptations will contribute to acclimatization in chronic hypoxia remains to be determined.
Explore the source record for details and available documents.
The volume of red blood cells (V(RBC)) is used routinely in the diagnostic workup of polycythemia, in assessing the efficacy of erythropoietin administration, and to study factors affecting oxygen transport. However, errors of various methods of measurement of V(RBC) and related parameters are not well characterized. We meta-analyzed 346 estimates of error of measurement of V(RBC) for techniques based on Evans blue (V(RBC,Evans)), 51chromium-labeled red blood cells (V(RBC,51Cr)), and carbon monoxide (CO) rebreathing (V(RBC,CO)), as well as hemoglobin mass with the carbon-monoxide method (M(Hb,CO)), in athletes and active and inactive subjects undergoing various experimental and control treatments lasting minutes to months. Subject characteristics and experimental treatments had little effect on error of measurement, but measures with the smallest error showed some increase in error with increasing time between trials. Adjusted to 1 day between trials and expressed as coefficients of variation, mean errors for M(Hb,CO) (2.2%; 90% confidence interval 1.4-3.5%) and V(RBC,51Cr) (2.8%; 2.4-3.2%) were much less than those for V(RBC,Evans) (6.7%; 4.9-9.4%) and V(RBC,CO) (6.7%; 3.4-14%). Most of the error of V(RBC,Evans) was due to error in measurement of volume of plasma via Evans blue dye (6.0%; 4.5-7.8%), which is the basis of V(RBC,Evans). Most of the error in V(RBC,CO) was due to estimates from laboratories with a relatively large error in M(Hb,CO), the basis of V(RBC,CO). V(RBC,51Cr) and M(Hb,CO) are the best measures for research on blood-related changes in oxygen transport. With care, V(RBC,Evans) is suitable for clinical applications of blood-volume measurement.