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D Polakovicová

Publications and source records attributed to D Polakovicová.

9 recordsLinked to original sources

Does magnesium dysbalance participate in the development of insulin resistance in early stages of renal disease?

We investigated the potential role of magnesium (Mg) dysbalance in the pathogenesis of insulin resistance (IR) in patients with mildly-to-moderately decreased renal function (creatinine: 142.8+/-11.0 mmol/l). The data were compared to those of 8 age- and sex-matched healthy controls (CTRL). The standard oral glucose tolerance test (oGTT) was performed in 61 patients. Twenty-two patients were classified as IR according to their values on fasting and after-load immunoreactive insulin concentrations. Serum and total erythrocyte Mg (tErMg) (atomic absorption spectro-photometry) and free erythrocyte Mg (fErMg) concentrations ((31) P NMR spectroscopy) were determined prior to and two hours after the glucose load. Ten out of 39 insulin-sensitive (IS) patients, but only one out of 22 insulin-resistant (IR) patients, had a low basal fErMg concentration (<162.2 micromol/l, chi2, p<0.01). IR patients had higher serum Mg, total erythrocyte Mg and bound erythrocyte Mg (bErMg) concentrations (both before and after glucose load) when compared with the IS group. Both groups responded to the glucose load with a significant decrease in serum Mg concentration (within the normal range), while the IR group also exhibited a decline in tErMg and bErMg. The mean sum of insulin needed to metabolize the same glucose load correlated positively with tErMg (r=0.545, p<0.01) and bErMg (r=0.560, p<0.01) in the IR patients. It is concluded that, at an early stage of renal dysfunction, IR is not associated with the decline in free erythrocyte Mg concentration, but the magnesium handling in red blood cells is altered.

Adult↗

Anti-hypertensive treatment with magnesium-aspartate-dichloride and its influence on peripheral serotonin metabolism in man: a subacute study.

Dichlormagnesium-aspartate-hydrochloride was given to 12 patients with mild hypertension in antihypertensive indication at a dose of 10.5 mmol Mg2+/day for 3 months. Blood pressure normalized (from 161.7 +/- 3.4/95.8 +/- 0.8 mmHg to 140.4 +/- 4.0/81.7 +/- 0.9 mmHg, after the third month (p < 0.01). While no changes in Mg2+ concentration in serum were observed in patients with normomagnesaemia, in hypomagnesaemic patients vS-Mg level normalized. Renal excretion of Mg2+ increased: from 3.41 +/- 0.36 before to 5.7 +/- 0.57 mmol Mg2+/24 h after treatment, p < 0.01. Mean plasma serotonin (5HT) concentration showed no changes, although a trend towards an increase in platelet 5HT content was observed. Elevated pre-treatment plasma 5-hydroxyindole acetic acid (5HIAA) concentrations normalized (from 137.29 +/- 20.3 to 78.96 +/- 31.64 nmol/l after the third month, p < 0.05). These findings point to a platelet-stabilizing effect of Mg2+. Fractional excretion of 5HIAA increased (from 1.42 +/- 0.27 to 5.4 +/- 1.22 after treatment, p < 0.01) while mean urinary 5HIAA excretion remained unchanged. It is deduced that a) total body 5HT and 5HIAA production was not affected; b) a long-term supplementation of Mg2+ stimulates the transport of 5HIAA in proximal tubules and, probably, intrarenal 5HIAA synthesis. A functional block in 5HT metabolism under Mg2+ treatment is anticipated. Thus, Mg2+ supplementation has renal and extrarenal effects that are important in treating hypertension and its complications.

Antihypertensive Agents↗

[The effect of a single administration of magnesium sulfate on glucose tolerance and insulinemia in healthy volunteers].

The effect of 2.0 g magnesium sulfate on glucose tolerance and immunoreactive insulin (IRI) response to glucose application was studied in 10 healthy normomagnesemic volunteers: a) Serum magnesium concentration (Mg) increased markedly and remained on the increased values during the study. Total erythrocyte Mg concentration did not change. b) The infusion application of 40 g glucose increased glykemia which returned promptly to fasting levels after the infusion termination. Mg did not influence the glycemic response. c) IRI concentration increased even more than glucose to the glucose load. Mg decreased the IRI response and even IRI/glucose ratio significantly. In conclusion, Mg increased insulin sensitivity even in healthy normomagnesemic subjects.

Adult↗

[A decrease in magnesium in the serum and blood lymphocytes after intravenous infusion of glucose].

The authors assessed in a group of 10 healthy volunteers the Mg content of serum, in erythrocytes (Er) and lymphocytes (Ly) before infusion and during three hours after infusion of 400 ml 10% glucose without added Mg and with addition of 10 ml 20% MgSO4 (magnesium sulphate, Spofa). It was revealed that glucose infusion without Mg reduces significantly serum magnesium as well as Mg in lymphocytes and the reduced values persist for at east three hours after termination of the infusion. In 3 of 10 volunteers the values dropped beneath the lower range of reference values; two of these three volunteers developed also clinical manifestations of Mg deficiency. Mg in Er was not affected by the glucose infusion. The glucose infusion with Mg raised significantly the serum Mg and Mg in Ly; Mg in Er did not change. Based on the submitted results the authors recommend prevention of Mg deficiency induced by glucose infusion by Mg supplementation, in particular in patients with cardiovascular diseases.

Adult↗

Blood lymphocyte magnesium in kidney stone formers.

Blood lymphocyte, serum and urinary magnesium analyses were performed in a randomized group of 36 kidney stone-formers with the aim to determine the incidence of intracellular and extracellular magnesium depletion in urolithiasis. Lymphocyte magnesium depletion was found in 10 patients, serum magnesium depletion in 5 and concomitant lymphocyte and serum magnesium depletion in another 3 patients. Thus intracellular and/or extracellular magnesium depletion was found in 15 patients (41.7%). Oral magnesium supplementation (5-10 mmol Mg2+ daily) was found in some patients ineffective in both lymphocyte and/or serum magnesium repletion.

Adolescent↗