Blockade of renin-angiotensin system reduces QT dispersion and improves intracellular Ca/Mg status in hemodialysis patients.

Background: Electrolyte impairments are common in hemodialysis (HD) patients. Consequently, QT dispersion (QTd) is prolonged, correlating with high intracellular magnesium. In patients with cardiac disorders, renin-angiotensin system (RAS) inhibition reduces QTd.

Renal functional deterioration is not affected by the magnitude of sodium consumption in a normotensive model of moderate renal failure.

Background/aims: High sodium consumption has been repeatedly reported to exert deleterious effects on severe chronic renal failure progression, mainly via glomerular mechanisms. However, the role of high sodium intake in renal function deterioration in a model of moderate chronic tubulointerstitial disease has not yet been addressed. We evaluated the effects of exaggerated dietary sodium and the resultant increase in proteinuria on renal function deterioration in experimental tubulointerstitial disease in rats.

Control of hypertension with captopril affords better renal protection as compared with irbesartan in salt-loaded uremic rats.

Background/aim: Hypertension induced by exaggerated sodium consumption accelerates the progression of renal failure. We investigated the effects of a high-sodium (HS) diet on the progression of renal failure in rats maintained normotensive by angiotensin-converting enzyme inhibition or AT-1 blockade.

Methods: In 70 Sprague-Dawley rats, renal failure was induced by five-sixths nephrectomy.

Loss of captopril-bound Fe by end-stage renal failure patients during hemodialysis.

Background: Patients on chronic hemodialysis often suffer from severe anemia, the outcome of iron deficiency and inadequate response to erythropoietin. Antihypertensive treatment with captopril worsens anemia, erythropoietin production and iron balance in hemodialysis patients. We investigated the possibility that iron chelation by captopril in the blood may result in elimination of iron-captopril complexes during hemodialysis, thus minimizing the effect of both medications.

Cell-associated magnesium and QT dispersion in hemodialysis patients.

Background: Impaired magnesium (Mg) homeostasis has been implicated in a variety of cardiovascular disturbances, including ventricular arrhythmias and changes in the interval between the onset of wave Q to the end of wave T (QT interval) on electrocardiogram. Cardiac arrhythmias are common in patients on hemodialysis therapy.

Methods: We investigated the relationship between QT interval corrected for heart rate (QTc) dispersion and Mg content in peripheral blood mononuclear cells (PBMC) of chronic hemodialysis patients treated with high-dose calcium carbonate providing Mg in excess (group I; n = 18) or low-dose calcium carbonate and smaller Mg load (group II; n = 13).