Department of Nuclear Biotechnique, Interuniversity Reactor Institute, Mekelweg 15, 2629, JB Delft, The Netherlands.
Biol Trace Elem Res. 1984 Dec;6(6):489-505. doi: 10.1007/BF02987203.
The influence of high but not extreme concentrations of Ca and Mg in water (25 µmol/mL) and of similar concentrations in food (25 µmol/g) on the absorption and retention of(54)Mn in mice was investigated. Addition of either Ca or Mg reduced the absorption of(54)Mn from water (administered by intragastric intubation) and from food (a portion made available for consumption during 1.5 h) by more than 50%. The retention of intraperitoneally injected(54)Mn was not influenced by addition of Ca or Mg (25 µmol/mL) to the drinking water. In mice fed a Ca-depleted diet during 2 wk prior to dosage, the absorption of(54)Mn from an intubated aqueous solution was increased by more than 100% compared to that in mice fed a Ca-adequate diet. In mice fed a Mg-depleted diet or a Ca- or Mg-replete diet for 2 wk, no changes in the absorption of(54)Mn were observed. In mice fed a Ca,Mg-depleted diet after(54)Mn administration, the turnover of absorbed(54)Mn was strongly increased, probably as a result of increased absorption of stable Mn from the diet. The results indicate that the uptake of Mn could be higher in soft water regions than in hard water regions.
研究了水中（25 μmol/ml）和类似浓度食物中（25 μmol/g）高但非极端浓度的 Ca 和 Mg 对小鼠（54）Mn 吸收和保留的影响。添加 Ca 或 Mg 均可使（54）Mn 从水（通过胃内插管给予）和从食物（在 1.5 小时内可食用的部分）中的吸收减少 50%以上。腹腔内注射（54）Mn 的保留不受饮用水中添加 Ca 或 Mg（25 μmol/ml）的影响。在给药前 2 周给喂食缺钙饮食的小鼠，与喂食含钙饮食的小鼠相比，从插管的水溶液中吸收（54）Mn 增加了 100%以上。在喂食缺镁或钙、镁充足饮食 2 周的小鼠中，未观察到（54）Mn 吸收的变化。在给予（54）Mn 后喂食缺钙、镁饮食的小鼠中，吸收的（54）Mn 的周转率大大增加，可能是由于从饮食中吸收稳定的 Mn 增加所致。结果表明，在软水地区，Mn 的摄取可能高于硬水地区。
