An evaluation of plasma and erythrocyte magnesium concentration and the activities of alkaline phosphatase and creatine kinase as indicators of magnesium status.
Rats were fed diets containing magnesium at concentrations ranging from 3.3 to 26.7 mmol/kg of diet (80 to 650 mg/kg). The magnesium concentration of their plasma and erythrocytes, and the activities of plasma alkaline phosphatase and creatine kinase were investigated to determine their usefulness as indices of magnesium status. All the indices increased with increasing dietary magnesium levels. The best correlations were observed between dietary intake and plasma concentration of magnesium (r = 0.846, p less than 0.001) and between intake and femur concentration (r = 0.811, p less than 0.001). There was an extremely high correlation between plasma concentration and femur concentration (r = 0.930, p less than 0.001). Although significant, the correlations between intake and the enzyme activities were not strong. It is concluded that plasma magnesium concentration is the most useful indicator of magnesium status and that the activities of the two magnesium-requiring enzymes can only be used for the purpose of diagnosing severely deficient magnesium status.
Fischer
P W
PW
Nutrition Research Division, Health and Welfare Canada, Ottawa, Ontario.
Giroux
A
A
D000469:Alkaline Phosphatase / Q000378:metabolism*; D000818:Animals; D003402:Creatine Kinase / Q000378:metabolism*; D004909:Erythrocyte Indices; D004912:Erythrocytes / Q000201:enzymology*; D005069:Evaluation Studies as Topic; D008274:Magnesium / Q000097:blood*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains
D003402:Creatine Kinase; D000469:Alkaline Phosphatase; D008274:Magnesium