OXYGEN AND CARBON DIOXIDE TRANSPORT BY THE BLOOD OF THE URODELE, AMPHIUMA TRIDACTYLA

Abstract

The 0 dissociation curve and CO2 absorption curves were determined by standard methods using in all about 20 animals. The corpuscular volume varies from 12 to 35% in different animals and the O capacity varies from 3 to 10 vol. %. The large nucleated corpuscles consume O rapidly and this source of error must be avoided by keeping the blood cold. The solubility of O in Amphiuma blood and serum, determined directly, was 92% of that of water for both blood and serum. The O dissociation curve is like the typical mammalian curve with certain features in common with those of the turtle and carp. The presence of physiological amounts of CO3 affects the O curve in the usual way. The comparative values of n and Ko of the Hill equation are given for the blood of Amphiuma, carp, turtle and man and the equation of Hill for these bloods held between 10-90 mm. O tension. The mechanism for the transport of CO2 in Amphiuma blood is much like that of the turtle and the flatness of the CO2 absorption curves is explained as a function of the limited amount of hemoglobin. The difference in the amount of CO2 carried by oxygenated and by reduced blood is quite small and probably has little physiological significance.