title: Parathyroid hormone effect on the fragility of human young and old red blood cells in uremia.
abstract: Parathyroid hormone (PTH) is elevated in patients with chronic renal failure (CRF) and was suggested to be one of the factors responsible for the anemic syndrome of these patients because it raises the osmotic fragility of the red blood cells (RBC). In the present study, the youngest and oldest RBC were separated from circulating erythrocytes by high-speed centrifugation. The age distribution was described, and the effect of PTH on the different age groups was investigated. Median density (MD) and glutamic-oxaloacetic transaminase (GOT) activity were chosen as age markers. MD (1.0985 +/- 0.00087) and GOT activity (12.49 +/- 2.083 IU/g Hb) of the young uremic cells did not differ significantly from the values of young normal cells (1.0987 +/- 0.00046 and 10.36 +/- 1.174 IU/g Hb, respectively). The MD of the oldest cells, however, was lower (1.1048 +/- 0.00054) and GOT was higher (6.60 +/- 1.1019 IU/g Hb) in the uremic than in the control cells (1.1093 +/- 0.00175 and 3.77 +/- 0.233 IU/g Hb, respectively). These results indicate that the life span of RBC in uremics is shorter than normal and that an enrichment of circulating RBC by young cells occurs in uremic patients. The median osmotic fragility (MOF) of the young cells was lower in both uremic (0.376 +/- 0.006) and control patients (0.378 +/- 0.003) than the MOF of old cells (0.402 +/- 0.005 and 0.392 +/- 0.004, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)
mesh_terms: D001219:Aspartate Aminotransferases / Q000097:blood; D002499:Centrifugation, Density Gradient; D004905:Erythrocyte Aging / Q000187:drug effects*; D004912:Erythrocytes / Q000201:enzymology; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood*; D009996:Osmotic Fragility / Q000187:drug effects; D010281:Parathyroid Hormone / Q000494:pharmacology*; D014511:Uremia / Q000097:blood / Q000628:therapy
chemical_list: D010281:Parathyroid Hormone; D001219:Aspartate Aminotransferases