Red cell sodium-lithium countertransport and blood pressure in children with insulin-dependent diabetes mellitus

Abstract Sodium-lithium countertransport and blood pressure responses, maximal elevated plasma norepinephrine concentrations induced by acute physical work load and the carbohydrate metabolic state were analyzed in 40 children suffering from insulin-dependent diabetes mellitus (IDDM). Patients were selected according to the duration of the disease to get a horizontal insight into the progression of the diabetes. Sixteen healthy children served as controls. Sodium-lithium countertransport (NaLi CT) was 281 ± 64 μmol/l red blood cells (RBC) per hour in the control group. NaLi CT was elevated in all diabetic groups (newly diagnosed: 455 ± 48; diabetics for 5–7 years: 495 ± 48; diabetics for 10–13 years: 470 ± 36). Plasma norepinephrine concentration increased during physical exercise, the elevation was more pronounced in diabetic children being 13.5 ± 10.4, 10.1 ± 5.0 and 12.3 ± 5.4 nmol/l in the three diabetic groups, respectively, which differed significantly from that of controls (7.94 ± 2.9; P P