Magnesium metabolism in erythrocytes of patients with chronic renal failure and after renal transplantation. Eur J Clin Chem Clin Biochem

Summary: Plasma and erythrocyte Mg24 " concentrations were found to be increased in 14 haemodialysis patients with chronic renal failure and in 7 chronic renal failure patients receiving chronic ambulatory peritoneal dialysis. The rate of Na+TMg2 * antiport was significantly higher in haemodialysis patients, but not in chronic ambulatory peritoneal dialysis patients (control: 0.15 ± 0.02, haemodialysis: 0.46 ± 0.08, chronic ambulatory peritoneal dialy-sis: 0.21 ± 0.06; Mg2"1", mmol/30 min X l cells). High erythrocyte Mg2+ content in chronic renal failure results from the increased plasma Mg2+, which induces elevated Mg2"1 " uptake during haematopoiesis. An increased rate of Na+/Mg2+ antiport, which only performs Mg2+ efflux, leads to a relatively lower erythrocyte Mg2+ content in haemodialysis patients compared with chronic ambulatory peritoneal dialysis patients. The elevated Na+/Mg24" antäport in erythrocytes from haemodialysis patients was almost normalised after haemodialysis. Incubation of normal erythrocytes with heat-inactivated plasma from haemodialysis patients led to a doubling of Na+/Mg2+ antiport, indicating the presence of a heat-stable, dialysable plasma factor. This factor does not accumu-late in chronic ambulatory peritoneal dialysis patients. After renal transplantation all changed quantities of Mg24" metabolism returned to normal. Introduction take up Mg2+ when incubated at increased extracellular Mg2"1 " concentration (6). On the other band, uraemi