食物单宁酸对根田鼠(Microtus oeconomus)钠平衡的作用

验证了单宁酸能引起植食性哺乳动物钠平衡的假设.在两种食物蛋白质水平条件下,测定了摄食含0%,3%和6%单宁酸食物的根田鼠的钠平衡和肾上腺肾小球的大小.结果表明,食物单宁酸能显著影响根田鼠的钠平衡,钠的丢失主要通过尿液.同时,单宁酸能显著影响试验个体的肾上腺肾小球的体积.初步研究显示,植食性哺乳动物对摄入的植物次生化合物的解毒引起机体钠平衡失调,而非植物次生化合物的消化抑制作用所致.

Dietary tannic acid modulate sodium balance in root voles (Microtus oeconomus)

This study tested the hypothesis that tannic acid can cause an imbalance of sodium of mammalian herbivores. The sodium balance and the size of the zona glomerulosa of the adrenal gland was measured in root voles fed a diet containing either low or high proteins supplemented with 0, 3, or 6% of tannic acid. Relative areas of adrenal regions (zona glomerulosa, combined zona fasciculata and zona reticularis (ZFZR)) of voles fed diets containing 6% of tannic acid were increased by 9% and 7.8% for low and high protein groups, respectively, compared with those in animals fed the control diets. ZFZR/cortex of voles fed a low or high protein diet containing 3% of tannic acid were increased by 14.31% and 6.5%, respectively, as compared with those of control groups. The results indicate that addition of tannic acid to a diet can significantly induce sodium excretion mainly through urine in root voles, which may affect sodium homeostasis. These results also suggest that detoxification rather than inhibition of digestibility may primarily contribute to the sodium imbalance of mammalian herbivores that are ingesting plant secondary compounds.