Tissue Magnesium Loss during Prolonged Hypokinesia in Magnesium Supplemented and Unsupplemented Rats

摘要

This study aims at showing that during hypokinesia (HK) tissue magnesium (Mg~(2+)) content decreases more with higher Mg~(2+) intake than with lower Mg~(2+) intake and that Mg~(2+) loss increases more with higher than lower tissue Mg~(2+) depletion due to inability of the body to use Mg~(2+) during HK. Studies were conducted on male Wistar rats during a pre-HK period and a HK period. Rats were equally divided into four groups: unsupplemented vivarium control rats (UVCR), unsupplemented hypokinetic rats (UHKR), supplemented vivarium control rats (SVCR) and supplemented hypoki-netic rats (SHKR). SVCR and SHKR consumed 42 mEq Mg~(2+) per day. The gastrocnemius muscle and right femur bone Mg~(2+) content decreased significantly, while plasma Mg~(2+) level and urine and fecal Mg~(2+) loss increased significantly in SHKR and UHKR compared with their pre-HK values and their respective vivarium controls (SVCR and UVCR). However, muscle and bone Mg~(2+) content decreased more significantly and plasma Mg~(2+) level, and urine and fecal Mg~(2+) loss increased more significantly in SHKR than in UHKR. The greater tissue Mg~(2+) loss with higher Mg~(2+) intake and the lower tissue Mg~(2+) loss with lower Mg~(2+) intake shows that the risk of higher tissue Mg~(2+) depletion is directly related to the magnitude of Mg~(2+)intake. The higher Mg~(2+) loss with higher tissue Mg~(2+) depletion and the lower Mg~(2+)loss with lower Mg~(2+) tissue depletion shows that the risk of greater Mg~(2+) loss is directly related to the magnitude of tissue Mg~(2+) depletion. It was concluded that tissue Mg~(2+) depletion increases more when