title: Modulation of 2,3-diphosphoglycerate 31P-NMR resonance positions by red cell membrane shape.
abstract: Na+ transport in the red cells of the dog is dependent on cell volume, a 20% change in cell volume leading to a 25-fold increase in apparent Na+ flux; the effect is dependent upon metabolic energy. We have found that swelling and shrinking dog red cells causes a shift in the 31P-NMR peak of 2,3-diphosphoglycerate, which is present in dog red cells at 5.5 mM. Control experiments indicate that the 2,3-diphosphoglycerate resonance peak shifts may not be attributed to: interaction with hemoglobin, changes in cell pH, ionic strength, diamagnetic susceptibility or small changes in the Mg2+/2,3-diphosphoglycerate ratio. Experiments with chlorpromazine and pentanol which alter red cell membrane area by a mechanism different from osmotic swelling suggest that 2,3-diphosphoglycerate interacts with a binding site in the cell that is dependent upon the physical condition of the dog red cell membrane.
mesh_terms: D000818:Animals; D001693:Biological Transport, Active; D002462:Cell Membrane / Q000187:drug effects / Q000648:ultrastructure*; D002746:Chlorpromazine / Q000494:pharmacology; D002794:Choline / Q000494:pharmacology; D004163:Diphosphoglyceric Acids / Q000097:blood* / Q000494:pharmacology; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D004912:Erythrocytes / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure*; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D000439:Pentanols / Q000494:pharmacology; D012964:Sodium / Q000097:blood; D013395:Sucrose / Q000494:pharmacology
chemical_list: D004163:Diphosphoglyceric Acids; D000439:Pentanols; D013395:Sucrose; D012964:Sodium; D002794:Choline; D002746:Chlorpromazine