Nielsen F H, Shuler T R, Zimmerman T J, Uthus E O
US Department of Agriculture, Grand Forks Human Nutrition Research Center, ND 58202.
Biol Trace Elem Res. 1988 Sep-Dec;17:91-107. doi: 10.1007/BF02795449.
A series of nine experiments were done to obtain further evidence that boron might be involved in major mineral metabolism (Ca, P, and Mg), thus indicating that boron is an essential nutrient for animals. Eight factorially arranged experiments of 6-10 wk durations were done with weanling Sprague-Dawley male rats. One factorially arranged experiment was done with weanling spontaneously hypertensive rats. The variables in each experiment were dietary boron supplements of 0 and 3 micrograms g, and dietary magnesium supplements of either 200 (Experiments 1-3) or 100 (Experiments 4-9) and 400 micrograms/g. In Experiments 7 and 9, a third variable was dietary manganese supplements of 25 and 50 micrograms/g. Methionine status was varied throughout the series of experiments by supplementing the casein-based diet with methionine and arginine. Findings were obtained indicating that the severity of magnesium deprivation and the methionine status of the rat strongly influence the extent and nature of the interaction between magnesium and boron, and the response to boron deprivation. When magnesium deprivation was severe enough to cause typical signs of deficiency, a significant interaction between boron and magnesium was found. Generally, the interaction was characterized by the deprivation of one of the elements making the deficiency signs of the other more marked. The interaction was most evident when the diet was not supplemented with methionine and especially when the diet contained luxuriant arginine. Signs of boron deprivation were also more marked and consistent when the diet contained marginal methionine and luxuriant arginine. Among the signs of boron deprivation exhibited by rats fed marginal methionine were depressed growth and bone magnesium concentration, and elevated spleen wt/body wt and kidney wt/body wt ratios. Because the boron supplement of 3 micrograms/g did not make the dietary intake of this element unusual, it seems likely that the response of the rats to dietary boron in the present study were manifestations of physiological, not pharmacological, actions, and support the hypothesis that boron is an essential nutrient for the rat.
进行了一系列九个实验，以获取更多证据证明硼可能参与主要矿物质代谢（钙、磷和镁），从而表明硼是动物必需的营养素。对断奶的斯普拉格-道利雄性大鼠进行了八项为期6至10周的析因实验。对断奶的自发性高血压大鼠进行了一项析因实验。每个实验的变量包括0和3微克/克的膳食硼补充剂，以及200（实验1-3）或100（实验4-9）和400微克/克的膳食镁补充剂。在实验7和9中，第三个变量是25和50微克/克的膳食锰补充剂。在整个系列实验中，通过在以酪蛋白为基础的饮食中补充蛋氨酸和精氨酸来改变蛋氨酸状态。研究结果表明，镁缺乏的严重程度和大鼠的蛋氨酸状态强烈影响镁和硼之间相互作用的程度和性质，以及对硼缺乏的反应。当镁缺乏严重到足以导致典型的缺乏症状时，发现硼和镁之间存在显著的相互作用。一般来说，这种相互作用的特征是一种元素的缺乏会使另一种元素的缺乏症状更加明显。当饮食中不补充蛋氨酸，尤其是当饮食中含有丰富的精氨酸时，这种相互作用最为明显。当饮食中含有边缘量的蛋氨酸和丰富的精氨酸时，硼缺乏的症状也更明显和一致。在喂食边缘量蛋氨酸的大鼠表现出的硼缺乏症状中，有生长受抑和骨骼镁浓度降低，以及脾脏重量/体重和肾脏重量/体重比值升高。由于3微克/克的硼补充剂并未使该元素的膳食摄入量异常，本研究中大鼠对膳食硼的反应似乎是生理作用而非药理作用的表现，并支持硼是大鼠必需营养素这一假设。
