Cell magnesium transport and homeostasis: role of intracellular compartments
Romani, A.; Marfella, C.; Scarpa, A.
Mineral and Electrolyte Metabolism 19(4-5): 282-289
1993
ISSN/ISBN: 0378-0392 PMID: 8264515 Document Number: 407515
Magnesium transport across the plasma membrane of cardiac and liver cells appears to be under hormonal control. The increase in cytosolic cAMP, following the adrenergic stimulation of both cell types, results in a major Mg-2+ efflux from perfused rat hearts or livers and from collagenase-dispersed ventricular myocytes or hepatocytes. By contrast, the activation of protein kinase C by carbachol, vasopressin, phorbol-myristate acetate or diacylglycerol analogs induces Mg-2+ accumulation in either of the experimental models. As for the role of intracellular compartments on Mg-2+ homeostasis, the cAMP-mediated Mg-2+ efflux largely depends on the mobilization of Mg-2+ from mitochondria via the mitochondrial adenine nucleotide translocase. By contrast, Mg-2+ influx appears to be related to the endo(sarco)plasmic reticulum and its dynamic handling of cytosolic Ca-2+.