Jia X, Emerick R J, Kayongo-Male H
Department of Chemistry and Biochemistry, South Dakota State University, Brookings 57007, USA.
Biol Trace Elem Res. 1997 Winter;59(1-3):113-22. doi: 10.1007/BF02783236.
A 2 x 2 x 3 factorial experiment was conducted to study the pH dependence of a silicon-iron interaction in vivo. The dietary treatments used in the factorial design were the following (mg/kg of diet): silicon, 0 and 500; iron, 35 and 187; acid-base, ammonium chloride as 0.5% of total diet (acidic), sodium bicarbonate as 1.0% of total diet (basic), or no supplementation of acid or base (control). The supplementation of 500 mg silicon/kg of diet increased plasma-iron concentration in rats fed the acidic or control diets, but not in rats fed the basic diet. A high dietary-iron level suppressed copper absorption and utilization and subsequently imposed a negative effect on its own utilization. An increase in the plasma total-cholesterol concentration caused by high dietary-iron level was likely a consequence of the antagonistic effect of iron on copper absorption and utilization. The use of cupric sulfate pentahydrate as the dietary-copper source in this study resulted in plasma copper concentrations that were approximately twice those obtained in a related study using cupric carbonate. Also, a 42% coefficient of variation (C.V.) for plasma-copper concentrations of rats fed cupric sulfate in this study was greatly reduced from the C.V. = 108% previously associated with the dietary cupric carbonate.
进行了一项2×2×3析因实验，以研究体内硅 - 铁相互作用对pH的依赖性。析因设计中使用的饮食处理如下（毫克/千克饮食）：硅，0和500；铁，35和187；酸碱，氯化铵占总饮食的0.5%（酸性），碳酸氢钠占总饮食的1.0%（碱性），或不补充酸或碱（对照）。在喂食酸性或对照饮食的大鼠中，每千克饮食补充500毫克硅会增加血浆铁浓度，但在喂食碱性饮食的大鼠中则不会。高饮食铁水平会抑制铜的吸收和利用，随后对其自身利用产生负面影响。高饮食铁水平导致的血浆总胆固醇浓度升高可能是铁对铜吸收和利用产生拮抗作用的结果。在本研究中使用五水硫酸铜作为饮食铜源导致血浆铜浓度约为在一项使用碳酸铜的相关研究中所获得浓度的两倍。此外，本研究中喂食硫酸铜的大鼠血浆铜浓度的42%变异系数（C.V.）较之前与饮食碳酸铜相关的108%的C.V.大幅降低。
