title: Erythrocyte phosphates and hemoglobin function in monotremes and some marsupials.
abstract: Hematologic values, red blood cell (RBC) organic phosphate composition, hemoglobin function, and hemoglobin composition have been determined on blood from the monotremes, the duckbill platypus and the echidna, and three species of marsupials, the Tasmanian devil, the wallaby, and the brush-tail possum. Blood from the platypus had a RBC count of 8.63 X 10(6)/mm3, a mean corpuscular volume of 49.1 millemicron3, and a white blood cell count of 26.0 X 10(3)/mm3. The RBCs from the monotremes and the three marsupials exhibited hemoglobin polymorphism, each with three hemoglobin components. Addition of ATP, 2,3-bisphosphoglycerate (2,3-P2-glycerate), or inositol pentakisphosphate (inositol-P5) to phosphate-free hemoglobin from each species decreased hemoglobin oxygen affinity; the order of effect of these compounds was ATP less than 2,3-P2-glycerate less than inositol-P5. The RBCs of all species had concentrations of 2,3-P2-glycerate ranging from 6.02 mumol/ml RBCs in the wallaby to 10.39 mumol/ml RBCs in the possum. The RBCs from the three species of marsupials had concentrations of ATP ranging from 0.24 mumol/ml RBCs in the possum to 0.80 mumol/ml RBCs in the Tasmanian devil. The level of ATP in RBCs of the platypus and echidna were 0.06 and 0.03 mumol/ml RBCs, respectively.
mesh_terms: D000255:Adenosine Triphosphate / Q000032:analysis / Q000494:pharmacology; D000818:Animals; D004912:Erythrocytes / Q000032:analysis*; D005988:Glyceric Acids / Q000494:pharmacology; D006454:Hemoglobins / Q000502:physiology*; D007294:Inositol / Q000494:pharmacology; D008394:Marsupialia / Q000097:blood*; D009007:Monotremata / Q000097:blood*; D010710:Phosphates / Q000032:analysis*; D010987:Platypus / Q000097:blood*; D004442:Tachyglossidae / Q000097:blood*
chemical_list: D005988:Glyceric Acids; D006454:Hemoglobins; D010710:Phosphates; D007294:Inositol; D000255:Adenosine Triphosphate