Background Information on the bioavailability of the essential mineral Mg2+ is sparse. Objective/Method Evaluation of the present knowledge on factors influencing the bioavailability and intestinal absorption of Mg2+. Results Mg2+ is absorbed via a paracellular passive and a transcellular active pathway that involves TRPM6/7 channel proteins. The bioavailability of Mg2+ varies within a broa...

The K+-insensitive component of Mg2+ influx in primary culture of ruminal epithelial cells (REC) was examined by means of fluorescence techniques. The effects of extracellular anions, ruminal fermentation products, and transport inhibitors on the intracellular free Mg2+ concentration ([Mg2+]i), Mg2+ uptake, and intracellular pH were determined. Under control conditions (HEPES-buffered high-NaCl...

Although the role of calcium (Ca2+) in the signal transduction and pathobiology of the exocrine pancreas is firmly established, the role of magnesium (Mg2+) remains unclear. We have characterized the intracellular distribution of Mg2+ in response to hormone stimulation in isolated mouse pancreatic acinar cells and studied the role of Mg2+ in modulating Ca2+ signaling using microspectrofluoromet...

In non Mg(2+)-loaded and non malaria-infected rat erythrocytes, mefloquine (100 micromol x l (-1)) stimulated choline/Mg2+ antiport without affecting the Na+/Mg2+ antiport. The stimulation of the choline/Mg2+ antiport by mefloquine, found in this study, and by trifluoperazine and fluvoxamine, reported previously [Ebel et al. Biochim Biophys Acta 2004; 1167: 132-40], was associated with CF3 grou...

TRPM6 and TRPM7 are distinct from all other ion channels in that they are composed of linked channel and protein kinase domains. Recent studies demonstrate that these 'chanzymes' are essential for Mg(2+) homeostasis, which is critical for human health and cell viability.

OBJECTIVE To show the effect of hypokinesia (HK; diminished movement) on magnesium (Mg2+) loss in Mg2+ deficient subjects and the effect of physical exercise and on Mg2+ deficiency with and without physical exercise: Mg2+ balance, serum Mg2+ concentration and Mg2+ loss were measured. METHODS Studies were conducted on 30 healthy male volunteers during a pre-experimental period of 30 days and a...

Mg2+ plays important roles in many physiological processes. However, the underlying molecular mechanisms, especially in the apoptotic pathway, remain unclear due to the diffusion of Mg2+ probes, which hinders long-term imaging in specific organelles. We developed an immobilized Mg2+ probe, MGH, which is covalently conjugated with the HaloTag protein in various organelles. HaloTag-coupled MGH en...

To study Mg2+ transport across the cell membrane, the cytoplasmic concentration of Mg2+ ([Mg2+](i)) in rat ventricular myocytes was measured with the fluorescent indicator furaptra (mag-fura-2) under Ca2+ -free conditions (0.1 mM EGTA) at 25 degrees C. The fluorescence ratio signal of furaptra was converted to [Mg2+](i) using calibration parameters previously estimated in myocytes (Watanabe and...

The plasma membrane of mammalian cells possesses rapid Mg2+ transport mechanisms. The identity of Mg2+ transporters is unknown, and so are their properties. In this study, Mg2+ transporters were characterized using a biochemically and morphologically standardized preparation of sealed rat liver plasma membranes (LPM) whose intravesicular content could be set and controlled. The system has the a...