Planells E, Llopis J, Perán F, Aranda P
Nutrition and Food Technology Institute, Virgen de las Nieves General Hospital, Granada, Spain.
J Am Coll Nutr. 1995 Jun;14(3):292-8. doi: 10.1080/07315724.1995.10718510.
The present study was undertaken to investigate the effect of dietary magnesium (Mg) deficiency on plasma levels of parathyroid hormone (PTH) and calcitonin (CT), and the changes in tissue calcium (Ca) and phosphorus (P) content.
Wistar rats were fed an Mg-deficient diet. Plasma levels of PTH and CT, and Ca and P content in plasma, whole blood, skeletal muscle, heart, kidney, femoral bone and brain, were determined after 7, 35, 42, 49, 56, 63 and 70 days.
Mg deficiency significantly increased plasma levels of ionic Ca after 1 week of deficiency, and significantly increased total Ca in plasma and whole blood after 5 weeks. Whole blood and plasma levels of P decreased significantly after 8 and 5 weeks, respectively, in comparison with values obtained in pair-fed control rats. Plasma levels of CT were not modified by hypercalcemia and hypomagnesemia. Plasma PTH decreased significantly during the first 3 weeks, then recovered gradually, reaching control values in week 7 and remaining stable thereafter, despite elevated levels of ionic Ca. The Mg-deficient diet led to calcification in skeletal muscle, heart, kidney and femur, detectable as early as week 5. However, P content increased only in kidney after 1 week, decreased in heart and femur after 5 weeks, and did not change in muscle. The Mg-deficient diet did not significantly modify Ca or P content in brain.
Mg deficiency led to tissue calcification and decreased P levels in blood, heart, and femur. These changes did not affect CT secretion. PTH appeared to be more closely related with hypomagnesemia than with hypercalcemia.
本研究旨在探讨膳食镁缺乏对甲状旁腺激素（PTH）和降钙素（CT）血浆水平的影响，以及组织钙（Ca）和磷（P）含量的变化。
给Wistar大鼠喂食缺镁饮食。在7、35、42、49、56、63和70天后，测定血浆中PTH和CT的水平，以及血浆、全血、骨骼肌、心脏、肾脏、股骨和大脑中的Ca和P含量。
缺镁1周后，离子钙血浆水平显著升高，缺镁5周后，血浆和全血中的总钙显著升高。与配对喂养的对照大鼠相比，全血和血浆中的P水平分别在8周和5周后显著降低。高钙血症和低镁血症未改变血浆CT水平。血浆PTH在前3周显著降低，然后逐渐恢复，并在第7周达到对照值，此后保持稳定，尽管离子钙水平升高。缺镁饮食导致骨骼肌、心脏、肾脏和股骨钙化，最早在第5周即可检测到。然而，P含量仅在1周后在肾脏中增加，在5周后在心脏和股骨中降低，在肌肉中没有变化。缺镁饮食对大脑中的Ca或P含量没有显著影响。
镁缺乏导致组织钙化，血液、心脏和股骨中的P水平降低。这些变化不影响CT分泌。PTH似乎与低镁血症的关系比与高钙血症的关系更密切。
