Effects of high calcium intake on bone metabolism in magnesium-deficient rats.
We examined the effects of high calcium (Ca) intake on bone metabolism in magnesium (Mg)-deficient rats. Male Wistar rats were divided into three groups, with each group having a similar mean body weight, and fed a control diet (control group), a Mg-deficient diet (Mg-deficient group) or a Mg-deficient Ca-supplemented diet (Mg-deficient Ca-supplemented group) for 14 d. Femoral Ca content was significantly lower in the Mg-deficient Ca-supplemented group than in the control group and Mg-deficient group. Femoral Mg content was significantly lower in the Mg-deficient group and Mg-deficient Ca-supplemented group than in the control group. Furthermore, femoral Mg content was significantly lower in the Mg-deficient Ca-supplemented group than in the Mg-deficient group. Serum osteocalcin levels (a biochemical marker of bone formation) were significantly lower in the two Mg-deficient groups than in the control group. As a biochemical marker of bone resorption, urinary deoxypyridinoline excretion was significantly higher in the Mg-deficient Ca-supplemented group than in the control group and Mg-deficient group. The results in the present study suggest that high Ca intake had no preventive effect on alteration of bone metabolism in Mg-deficient rats.
Matsuzaki
H
H
Department of Nutrition, Junior College of Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 156-8502, Japan.
Katsumata
S I
SI
Uehara
M
M
Suzuki
K
K
Nakamura
K
K
D000042:Absorption; D000596:Amino Acids / Q000652:urine; D000818:Animals; D001842:Bone and Bones / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D002136:Calcium, Dietary / Q000008:administration & dosage*; D004435:Eating / Q000187:drug effects; D005269:Femur / Q000378:metabolism; D008275:Magnesium Deficiency / Q000378:metabolism*; D008297:Male; D015675:Osteocalcin / Q000097:blood; D051381:Rats; D017208:Rats, Wistar
D000596:Amino Acids; D002136:Calcium, Dietary; D015675:Osteocalcin; C036020:deoxypyridinoline; D002118:Calcium