Erythrocyte 2,3-DPG, PO2 50% and available O2 during the early post-natal fall in hemoglobin in rabbits.
Erythrocyte 2,3-DPG, PO2 50%, whole blood hemoglobin and available O2, and fixed acid Bohr effect were studied during the first 10 days after birth in rapidly growing suckling rabbits. The post-natal fall in hemoglobin concentration was accompanied by a marked rise in erythrocyte 2,3-DPG and a gradual increase in PO2 50%. The rise in PO2 50% was sufficient to keep the available O2 of the blood unchanged throughout the observation period. The observations show that a 2,3-DPG mediated rise in PO2 50% very effectively contributes to maintenance of adequate tissue oxygenation during the post-natal fall in hemoglobin. The rise in 2,3-DPG and and PO2 50% may be due to the ordinary hypoxia-induced shift to the right of the hemoglobin O2 dissociation curve, as observed under other circumstances when blood hemoglobin is rapidly reduced, but the very marked rise in 2,3-DPG and the very low delta PO2 50%/delta 2,3-DPG ratio suggest that the rise may as well be due to hypoxia independent, pre-programmed processes. The fixed acid Bohr effect was essentially the same in newborn and adult rabbits, and was uninfluenced by large variations in 2,3-DPG.
D019794:2,3-Diphosphoglycerate; D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D004163:Diphosphoglyceric Acids / Q000097:blood*; D004912:Erythrocytes / Q000378:metabolism*; D006454:Hemoglobins / Q000032:analysis*; D010087:Oxides / Q000097:blood; D010100:Oxygen / Q000097:blood*; D010758:Phosphorus / Q000097:blood; D011817:Rabbits; D013458:Sulfur Dioxide / Q000097:blood
D004163:Diphosphoglyceric Acids; D006454:Hemoglobins; D010087:Oxides; D013458:Sulfur Dioxide; D019794:2,3-Diphosphoglycerate; D010758:Phosphorus; D010100:Oxygen