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Assessment of Pulmonary Capillary Blood Volume, Membrane Diffusing Capacity, and Intrapulmonary Arteriovenous Anastomoses During Exercise
Published on: February 20, 2017
Rate of CO uptake by canine erythrocytes as a function of PO2
R O Crapo1, N Bitterman, S L Berlin
1Department of Physiology, School of Medicine, University of Pennsylvania, Philadelphia 19104.
Abstract:
We used a continuous-flow rapid-mixing apparatus with spectroscopic analysis to measure the rate of CO uptake by canine erythrocytes at 37 degrees C at five different PO2 values from 0 to 553 Torr. Fresh blood from five different dogs was used for the experiments. PCO approximated 80 Torr. Corrections for the lower capillary PCO during a measurement of the diffusing capacity of lung CO, as made by Roughton and Forster in 1957 (J. Appl. Physiol. 11: 290-302, 1957), were not used. The regression equation for 1/theta, where theta is milliliters of CO combining for each milliliter of whole blood (capacity 0.2 ml/ml) per minute for a PCO of 1 Torr was 1/theta = 1.45 +/- 0.0042 PO2. This equation is very similar to that for human erythrocytes under the same conditions.
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