Distribution of magnesium in the arterial wall.
1. The Mg, Ca, Na and K content were determined in the rat tail artery in vitro under various experimental conditions.2. The arterial Mg could be varied selectively at a constant [Mg](o) by altering the content of intracellular compounds capable of forming complexes with Mg(2+) such as nucleoside-5'-triphosphates or citrate.3. The release of tissue Mg during incubation in Mg-free solutions was found to consist of a fast and a slow component. The size of the fast component was dependent on the original [Mg](o). The size of the slow component was dependent on the content of intracellular compounds forming complexes with Mg(2+). The rate of efflux of the slow component could be increased by increasing [Mg(2+)](i), by removing external Ca, or by making the artery metabolically inactive.4. The results seem to indicate that [Mg(2+)](i) in metabolically active vascular smooth muscle cells is maintained at a level of ca. 10(-4)M.
D000332:Aerobiosis; D000693:Anaerobiosis; D000818:Animals; D001158:Arteries / Q000378:metabolism*; D001639:Bicarbonates / Q000378:metabolism; D001693:Biological Transport, Active; D002118:Calcium / Q000378:metabolism; D002951:Citrates / Q000378:metabolism; D005110:Extracellular Space / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D006601:Hexoses / Q000378:metabolism; D008274:Magnesium / Q000378:metabolism*; D008297:Male; D009130:Muscle, Smooth / Q000378:metabolism; D009994:Osmolar Concentration; D010710:Phosphates / Q000378:metabolism; D011188:Potassium / Q000378:metabolism; D051381:Rats; D012964:Sodium / Q000378:metabolism; D013431:Sulfates / Q000378:metabolism; D013997:Time Factors
D001639:Bicarbonates; D002951:Citrates; D006601:Hexoses; D010710:Phosphates; D013431:Sulfates; D012964:Sodium; D008274:Magnesium; D005947:Glucose; D011188:Potassium; D002118:Calcium