phosphorus-radioisotopes and Spherocytosis--Hereditary

The phosphorylation state of the proteins in hereditary spherocytosis erythrocyte membranes, incubated in the presence of [gamma-32P]ATP, appears to be different from that in normal ones. This is indicated by the finding that in the two types of erythrocyte membranes the ratios between the 32P-labeling of their phosphorylserine and phosphorylthreonine residues were different.

Topics: Adenosine Triphosphate; Blood Protein Electrophoresis; Erythrocyte Membrane; Erythrocytes; Humans; In Vitro Techniques; Membrane Proteins; Phosphates; Phosphorus Radioisotopes; Spherocytosis, Hereditary; Time Factors

Evidence has been recently presented of a relative deficiency of Ca2+ - dependent adenosine triphosphatase activity of erythrocyte membranes obtained from patients with hereditary spherocytosis. We have sought to confirm these findings by measuring calcium efflux from intact erythrocytes of patients with hereditary spherocytosis, as well as erythrocyte calcium concentrations, but find both these parameters to be normal. Ca2+-dependent adenosine triphosphatase activity, as well as Ca2+ -dependent membrane phosphorylation was also not found to be deficient in erythrocyte membranes from subjects with hereditary spherocytosis. These studies do not support the postulate that an accumulation of calcium affects the deformability of erythrocytes and their subsequent destruction in the spleen.

Topics: Adenosine Triphosphatases; Adenosine Triphosphate; Aspartate Aminotransferases; Calcium; Cations, Divalent; Cell Membrane Permeability; Erythrocyte Membrane; Erythrocytes; Humans; Phosphorus Radioisotopes; Spherocytosis, Hereditary

Radionuclide studies of the erythron are valuable to the physician in evaluating the clinical situation in a wide variety of hematologic disorders. A complete and accurate analysis of the life cycle of the red cell can be obtained with a full iron kinetic study, in conjunction with a DF32P red-cell survival study. However, a complete iron kinetic study is not always necessary. It may be abbreviated by deleting the in vitro phase of the iron kinetic procedure. The abbreviated iron kinetic study is also done in conjunction with a DF32P red-cell survival study. It can easily be performed by injecting 59Fe-labeled plasma and monitoring externally over the spleen, liver, and sacrum. Measurements of red-cell survival may be obtained with either 51Cr or DF32P. Although 51Cr provides a relatively uniform label of circulating red cells and is convenient to count in vitro, its highly variable elution rate precludes an accurate measurement of erythrocyte survival. The 51Cr method provides only a rough index of circulating red-cell half-times as a measure of red-cell survival. DF32P, HOWEVER, IS A PERMANENT LABEL OF CIRCULATING RED CELLS. It provides a direct measurement of erythrocyte survival and permits in vivo labeling of red cells simply by means of direct intravenous injection. Because it has an elution rate that is virtually zero after minimal elution on the day of injection, and because it is not reutilized, DF32P is unquestionably the best agent known for the determination of red-cell survival. In addition to these diagnostic data, the complete iron kinetic study can provide data on the deposition of iron in storage and the rate of iron storage exchange. It can also determine if erythropoiesis is quantitatively abnormal and if the abnormality is located in the bone marrow or in other organs such as the liver or spleen. Although the study of hematologic disorders is one of the most rapidly developing areas of medical research, techniques that are currently available can provide an understanding of the life cycle of the red cell and valuable data that can be applied directly to the clinical situation. When performed accurately, these studies provide a thorough analysis of the pathophysiology of the erythron and are valuable clinical tools that can be used successfully in the diagnosis and evaluation of a broad spectrum of hematological disorders.

Topics: Anemia; Anemia, Hemolytic; Anemia, Hemolytic, Autoimmune; Anemia, Hypochromic; Anemia, Pernicious; Bone Marrow Diseases; Cell Survival; Chromium Radioisotopes; Erythrocytes; Hemochromatosis; Hemoglobinuria, Paroxysmal; Hemosiderosis; Humans; Iron Radioisotopes; Isoflurophate; Isotope Labeling; Leukemia; Phosphorus Radioisotopes; Polycythemia Vera; Primary Myelofibrosis; Radioisotopes; Radionuclide Imaging; Spherocytosis, Hereditary; Splenic Diseases; Vitamin E Deficiency

Topics: Adenosine Triphosphatases; Biological Transport, Active; Cell Membrane Permeability; Chromium Radioisotopes; Erythrocytes; Humans; Osmotic Fragility; Ouabain; Phosphorus Radioisotopes; Potassium; Reticulocytes; Sodium; Sodium Isotopes; Spherocytosis, Hereditary; Spleen; Splenectomy

Topics: Blood Protein Electrophoresis; Blood Proteins; Cell Membrane; Cyclic AMP; Dithiothreitol; Electrophoresis, Polyacrylamide Gel; Erythrocytes; Humans; Molecular Weight; Phosphorus Radioisotopes; Protein Kinases; Sodium Dodecyl Sulfate; Spherocytosis, Hereditary; Spleen; Splenectomy; Time Factors

Topics: Adult; Aged; Anemia, Hemolytic; Anemia, Hypochromic; Anemia, Macrocytic; Bone Marrow; Cell Survival; Erythrocytes; Erythropoiesis; Female; Hematologic Diseases; Hemoglobins; Humans; Iron; Iron Radioisotopes; Isoflurophate; Leukemia, Lymphoid; Liver Cirrhosis; Male; Methods; Middle Aged; Phosphorus Radioisotopes; Polycythemia; Spherocytosis, Hereditary; Thalassemia