phosphorus-radioisotopes and Diabetes-Mellitus

Topics: Bone and Bones; Diabetes Mellitus; Femur Head Necrosis; Foot Diseases; Hip Prosthesis; Humans; Phosphorus Radioisotopes; Radionuclide Imaging

We studied metabolic pool size of polyphosphoinositides and phosphatidate of erythrocyte membranes from normal and diabetic subjects using 32P for 20-h incubation, a sufficiently long period to reach isotopic equilibrium between monoesterphosphate bond and gamma-phosphate of ATP. Phosphatidylinositol 4-monophosphate (PtdIns4P), phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P2) and phosphatidate were the phospholipids labelled. Metabolic pools of individual phospholipids were estimated, based on their proportionate and absolute radioactivity. A significant decline in radioactivity of phosphatidate and PtdIns(4,5)P2 was seen in erythrocytes from the diabetic subjects, indicating suppression of the metabolically labile pool of these two phospholipids. There was no significant change in PtdIns4P radioactivity between the groups. The direct effect of insulin on phosphorylation of polyphosphoinositides and phosphatidate was also evaluated by a short incubation period of erythrocyte membranes with [gamma-32P]-ATP. Added insulin increased the incorporation of 32P into phosphatidate in a dose-dependent manner that reached a steady state at 2 nM. We conclude that the metabolically labile pool size of phosphatidate is decreased and that of polyphosphoinositides is altered in erythrocyte membranes from diabetic patients.

Topics: Adenosine Triphosphate; Diabetes Mellitus; Erythrocyte Membrane; Female; Humans; Kinetics; Male; Membrane Lipids; Middle Aged; Phosphatidic Acids; Phosphatidylinositol Phosphates; Phosphatidylinositols; Phospholipids; Phosphorus Radioisotopes; Reference Values; Regression Analysis

Topics: Adenylyl Cyclases; Animals; Biological Transport; Calcium; Chromatography, Ion Exchange; Chromatography, Paper; Diabetes Mellitus; Glucosephosphates; Glycogen; Glycogen Synthase; Male; Microscopy, Electron; Muscles; Phosphoric Diester Hydrolases; Phosphorus Radioisotopes; Streptozocin; Subcellular Fractions; Time Factors; Tritium; Ultracentrifugation

Topics: Adenylyl Cyclases; Adipose Tissue; Animals; Diabetes Mellitus; Disease Models, Animal; Epinephrine; Lipid Metabolism; Male; Metabolism; Mice; Mice, Inbred C57BL; Mice, Inbred Strains; Phosphoric Diester Hydrolases; Phosphorus Radioisotopes; Tritium

Topics: Adult; Diabetes Complications; Diabetes Mellitus; Erectile Dysfunction; Humans; Male; Middle Aged; Phosphorus Radioisotopes; Spermatogenesis; Testis; Time Factors

Topics: Adipose Tissue; Adrenal Glands; Adrenalectomy; Animals; Caseins; Cyclic AMP; Diabetes Mellitus; Enzyme Activation; Kinetics; Liver; Male; Phosphorus Radioisotopes; Protein Binding; Protein Kinases; Rats; Streptozocin; Tritium

Topics: Adrenalectomy; Animals; Body Weight; Diabetes Mellitus; Dogs; Glucose; Hypophysectomy; Injections, Intravenous; Insulin; Phosphorus; Phosphorus Radioisotopes; Stimulation, Chemical; Thyroidectomy