Sulphate Influx in the Erythrocytes of Normotensive, Diabetic and Hypertensive Patients

Abstract

This study aimed to show that modifications in intracellular metabolism are implicated in the pathophysiology of diabetes mellitus and essential hypertension. In fact, total magnesium, calcium, sodium and potassium concentrations, measured in the erythrocytes of normotensive, diabetic and hypertensive patients, have given the following results: a lower intracellular potassium concentration in the erythrocytes of diabetic and hypertensive patients than the erythrocytes of normotensive patients and a more elevated sodium, magnesium, calcium concentrations in the erythrocytes of diabetic and hypertensive patients than the normotensive. Because of the importance of Mg2+ and Ca2+ in metabolic enzyme regulation and their interaction with both Hb and band 3 protein, we examined SO4(2-) kinetic influx in the erythrocytes of normotensive, hypertensive and diabetic patients. The kinetic plots showed different profiles over the three groups and the fluxes were found to be 0.024, 0.061 and 0.072 mmol x (l cells x min)(-1) in normotensive, hypertensive and diabetic patients, respectively. We also found that the Vmax and Km of sulphate influx, obtained by Hofstee plots, increased in the erythrocytes of hypertensive and diabetic patients compared with control cells. In contrast, sulphate influx in the erythrocytes of diabetic and hypertensive patients in the presence of Nifedipine, a calcium antagonist, showed no difference either in the rate constants or in the kinetic profiles, compared to the normotensive control subjects.

Sulphate and Chloride-Dependent Potassium Transport in Human Erythrocytes are Affected by Crude Venom from Nematocysts of the JellyfishPelagia noctiluca

“…At specified intervals, 5 ml samples of the suspensions were removed and added to a test tube containing 5µM 4,4'-diisothiocyanato-stilbene-2,2'-disulfonate (DIDS) stopping medium (10 ml) and kept on ice. The presence of DIDS, a compound that binds irreversibly and specifically to the extracellular moiety of the integral membrane Band 3 protein, inhibits SO 4 2- transport in erythrocytes [23]. …”

Erythrocyte Aging: A More than Superficial Resemblance to Apoptosis?

“…At the moment both hypotheses remain unfalsified, probably for a number of reasons: 1, changes in the cytoplasmic domain of band 3 affect structure and function of the membrane domain and vice versa, which makes it difficult to pinpoint the original site of disturbance; 2, because of the central role of band 3 in erythrocyte homeostasis, many processes induce changes in band 3, including erythrocyte-specific pathology but possibly also other conditions such as old age, pregnancy, cardiovascular pathology, and diabetes [26][27][28]. In addition, the presence of denatured hemoglobin per se, such as in unstable hemoglobinopathies, is not clearly associated with a accelerated erythrocyte aging phenotype [29].…”

Effects of Nickel on Human and Fish Red Blood Cells

“…At specified intervals, 5 ml samples of the suspension were removed and added to a test tube containing 5 lM 4,4¢-diisothiocyanato-stilbene-2,2¢-disulfonate (DIDS) stopping medium and kept in ice. DIDS, a compound that binds irreversibly and specifically to the band 3 protein, inhibits SO 4 2-transport in both human and fish red blood cells (Lepke et al 1976;Romano et al 2002;De Luca et al 2004). After withdrawal of the last sample, the erythrocytes were washed three times in a sulphate-free medium at 0°C to remove extracellular sulphate, then lysed with 1 ml distilled water and 100 ll trichloroacetic acid at 99%.…”