Chronic EtOH administration alters liver Mg2+ homeostasis.
Ethanol (EtOH) administration to rats for 4 wk markedly decreased Mg(2+) content in several tissues, including liver. Total cellular Mg(2+) accounted for 26.8 +/- 2.4 vs. 36.0 +/- 1.4 nmol Mg(2+)/mg protein in hepatocytes from EtOH-fed and control rats, respectively, and paralleled a 13% decrease in cellular ATP content. Stimulation of alpha(1)- or beta-adrenergic receptor or acute EtOH administration did not elicit an extrusion of Mg(2+) from liver cells of EtOH-fed rats while releasing 5% of total tissue Mg(2+) content from hepatocytes of control rats. Despite the 25% decrease in Mg(2+) content, hepatocytes from EtOH-fed rats did not accumulate Mg(2+) following stimulation of protein kinase C signaling pathway, whereas control hepatocytes accumulated approximately 2 nmol Mg(2+). mg protein(-1). 4 min(-1). Together, these data indicate that Mg(2+) homeostasis and transport are markedly impaired in liver cells after prolonged exposure to alcohol. The inability of liver cells, and possibly other tissues, to accumulate Mg(2+) can help explain the reduction in tissue Mg(2+) content following chronic alcohol consumption.
Young
Andrew
A
Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, Ohio 44106-4970, USA.
Cefaratti
Christie
C
Romani
Andrea
A
D000322:Adrenergic Agonists / Q000494:pharmacology; D000818:Animals; D002462:Cell Membrane / Q000378:metabolism; D002492:Central Nervous System Depressants / Q000494:pharmacology*; D000431:Ethanol / Q000494:pharmacology*; D022781:Hepatocytes / Q000378:metabolism; D006706:Homeostasis / Q000187:drug effects; D008099:Liver / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D008274:Magnesium / Q000378:metabolism*; D008297:Male; D011493:Protein Kinase C / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology
D000322:Adrenergic Agonists; D002492:Central Nervous System Depressants; D000431:Ethanol; D011493:Protein Kinase C; D008274:Magnesium