The oxygen affinity of chicken haemoglobin in whole blood and erythrocyte suspensions.
The oxygen equilibrium of whole chicken blood has a P50 of 52.3 mm Hg and a Hill coefficient of 2.6 at pH 7.4 and 37 degrees C when determined with new microtechniques which are not vitiated by cellular respiration. The apparent failure of the haemoglobin to reach full saturation at arterial PO2 IS DISCUSSED IN RELATION TO THE HAEMoglobin-oxygen equilibrium concept. The low affinity observed is due to intraerythrocytic inositol pentaphosphate (IPP), and the affinity of a haemolysate "stripped" of IPP is greatly increased (deltalog P50 =1.25). Unlike the mamalian analogue 2, 3-diphosphoglycerate, IPP concentration of whole blood does not decrease after incubation for 10 hr at 37 degreesC.
D000328:Adult; D000818:Animals; D002645:Chickens / Q000378:metabolism*; D004912:Erythrocytes / Q000378:metabolism*; D005260:Female; D006454:Hemoglobins / Q000378:metabolism*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007294:Inositol / Q000097:blood / Q000494:pharmacology; D008297:Male; D010100:Oxygen / Q000097:blood*; D010101:Oxygen Consumption; D010108:Oxyhemoglobins / Q000378:metabolism
D006454:Hemoglobins; D010108:Oxyhemoglobins; D007294:Inositol; D010100:Oxygen