losartan-potassium and Hyperinsulinism

Ten patients (18 +/- 1 yr) on chronic hemodialysis (HD) with anemia were studied before and after treatment with erythropoietin (EPO) for 9 mo. Six patients had evidence of iron overload (serum ferritin over 300 ng/ml; group I) and the other four patients (serum ferritin below 300 ng/ml; group II) did not. Before treatment, both groups of patients were glucose tolerant but insulin resistant and hyperinsulinemic. There was equal correction of anemia but no significant changes in serum biochemistry (apart from iron studies) or anthropometric measurements in both groups. With amelioration of anemia and iron overload in group I, insulin sensitivity increased by 53% to within normal values. Insulin secretion also normalized. With amelioration of anemia but no change in iron status in group II, insulin sensitivity (increased by 60%) and insulin secretion also normalized. Thus correction of anemia by EPO reversed insulin resistance and hyperinsulinemia in HD patients with or without iron overload. The effects of correction of anemia rather than iron overload may be more important in the pathogenesis of insulin abnormalities in end-stage renal disease.

Topics: Adolescent; Adult; Anemia; Erythropoietin; Ferritins; Glucose Clamp Technique; Glucose Tolerance Test; Humans; Hyperinsulinism; Insulin Resistance; Kidney Failure, Chronic; Renal Dialysis; Uremia

The pathogenesis of the increased erythrocytosis and extramedullary erythropoiesis observed in infants of diabetic mothers (IDM) has been obscure. In the present studies, IDM were found to have elevated umbilical plasma erythropoietin (Ep) concentrations by radioimmunoassay. 22 of 61 IDM (36%) had levels above the range of 28 nonasphyxiated, appropriately grown normal infants. In 16 controls and 20 IDM, plasma Ep correlated directly with plasma insulin (P less than 0.001, r = 0.73). To investigate this relationship further, a chronic rhesus model was studied with continuous fetal hyperinsulinemia for 21 d in utero in the last third of pregnancy. In five experimental fetuses, plasma insulin levels averaged 4,210 microU/ml at delivery, whereas plasma Ep was above the range of six controls. In addition, the experimental fetuses had elevated reticulocyte counts in umbilical cord blood. The mechanism for the increased plasma Ep associated with hyperinsulinemia in the fetus is unexplained but may be mediated by fetal hypoxia.

Topics: Animals; Blood Glucose; Carbohydrate Metabolism; Diabetes Mellitus; Disease Models, Animal; Erythropoiesis; Erythropoietin; Female; Fetal Blood; Hemoglobin A; Humans; Hyperinsulinism; Insulin; Macaca mulatta; Pregnancy; Pregnancy in Diabetics