Oxygenation and deoxygenation velocity factors of chorioallantoic capillary blood

The oxygenation and deoxygenation rates of capillary blood of chicken embryo were measured precisely with a microphotometric reaction apparatus. The velocity factors expressed as Fcox and Fcdeox in ml O2-ml RBC-1-S-1-mmHg-1 were calculated as functions of oxygen saturation. They were similar to results previously obtained in human blood using the rapid flow apparatus. The continuous registration of the reaction with oxygen enables us to estimate the equilibrium time of blood when passing through the chorioallantoic capillary. The value obtained was almost identical to the contact time indirectly assessed from the CO reaction. The diffusing capacity of the chorioallantoic capillary plexus of the 16-day-old embryos was estimated as 7.3 x 10(-3) ml-min-1mmHg-1 by using the values of the Fcox and the equilibrium time determined here together with the values of the blood flow and hematocrit which had been obtained in the previous experiments.