Abstract
A new method to determine total Mg++ content in lymphocytes was developed, offering advantages for routine measurements
as compared to fluorescence methods. Intracellular total Mg++ measurements were performed in lymphocytes of 18 healthy subjects and 19 untreated
essential hypertensive patients. Mg++ content was referred to lymphocytic and membrane protein, which was determined according
to Bradford's method. Mg++ measurements were performed by atomic absorption spectroscopy using a Video 12 apparatus
of Thermo Electron Instrumentation Laboratory, Andover, USA. The results show that
in patients with essential hypertension total intralymphocytic Mg++ content is significantly lower (0.07 ± 0.05 mmol/g lymphocytic protein, mean ± s.d.)
as compared to controls (0.11 ± 0.04 mmol/g lymphocytic protein, mean ± s.d., p <
0.05).
Free intracellular Mg++ content was measured in lymphocytes by the fluorescent indicator mag-fura-II, showing
no significant differences in normotensives and hypertensives (0.30 ± 0.16 versus
0.38 ± 0.17 mmol/l). Additionally, in platelets free intracellular Mg++ concentrations were not found of significant difference in normotensives and hypertensives
(0.52 ± 0.23 versus 0.47 ± 0.27 mmol/l) using mag-fura-II. In plasma Mg++ concentrations there was no significant difference in the normotensive and hypertensive
group (0.92 ± 0.07 versus 0.88 ± 0.07 mmol/l). There was no correlation between plasma
or free or total cellular magnesium concentrations in both groups. Furthermore this
method seems also suitable for routine measurements of total intracellular Mg++ concentrations in even larger measurements like mag-fur-II. Lowered total intracellular
Mg++ concentrations in a subgroup of primary hypertensives may contribute to the development
of this disorder, perhaps due to different buffering systems.
