[Aging and homeostasis. Calcium metabolism and aging.]
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Updated: Feb 27, 2026

Ex Vivo Assessment of Contractility, Fatigability and Alternans in Isolated Skeletal Muscles
Published on: November 1, 2012
1Fujii Memorial Institute of Medical Sciences, Institute of Advanced Medical Sciences, Tokushima University, Japan.
Abstract:
About 99% of total body calcium is present in bone. Therefore, negative calcium balance usually means reduction of bone mass. Negative calcium balance is induced by aging from several mechanisms such as reduced renal production of 1,25-dihydroxyvitamin D[1,25(OH) 2 D], intestinal resistance to 1,25(OH) 2 D and increased renal excretion of calcium. However, it is largely unknown how calcium balance is physiologically maintained.
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