ZINC, IRON, AND COPPER ABSORPTION IN THE STREPTOZOTOCIN-DIABETIC RAT
ZINC, IRON, AND COPPER ABSORPTION IN THE STREPTOZOTOCIN-DIABETIC RAT
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DOI：
10.1152/ajpendo.1983.244.2.e122
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发表时间：
1983-01-01
影响因子：
--
通讯作者：
FAILLA, ML
中科院分区：
文献类型：
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作者：
CRAFT, NE;FAILLA, ML
据报道，链脲佐菌素糖尿病(STZ)大鼠的组织中痕量金属水平发生了变化。为了确定肝脏和肾脏中铜和锌水平的增加是否与肠道吸收增加有关，采用膳食平衡和原位结扎环技术，研究了对照组(C)和STZ大鼠对微量金属的吸收。每100g体重的膳食锌和铜的日表观摄入量，STZ组是C组的3倍。相比之下，膳食铁的日吸收率没有变化。锌吸收增加与糖尿病相关的多食症密切相关。注射~(65)Zn后，STZ大鼠的初始排泄速度比STZ大鼠快，但第7天以后的排泄速度与C和STZ大鼠相似。C组和STZ组大鼠每20 cm十二指肠环吸收的锌、铁、铜的量相似。STZ大鼠每克干粘膜对锌、铁、铜的吸收因粘膜质量增加50%而减少45%-53%。此外，C组和STZ组每克干粘膜中放射性同位素的积累量和每克粘膜胞浆蛋白中金属硫蛋白的浓度相似。综上所述，这些数据表明，膳食锌和铜的吸收增加在一定程度上是这些元素在STZ组织中积累的原因，并表明肠道上皮腔(刷缘)表面的金属运输发生了变化。
Altered tissue levels of trace metals have been reported in streptozotocin-diabetic (STZ) rats. To determine whether increased hepatic and renal levels of Cu and Zn were associated with enhanced intestinal absorption, trace metal absorption was studied in control (C) and STZ rats using dietary balance and in situ ligated-loop techniques. The apparent daily absorption of dietary Zn and Cu per 100 g body wt was 3-fold higher in STZ than C rats. In comparison, dietary Fe absorption per day was not altered. Increased Zn absorption was closely correlated with diabetes-associated polyphagia. The initial rate of injected 65Zn excretion was more rapid in STZ rats, although the rate of excretion beyond day 7 was similar from C and STZ animals. The quantity of Zn, Fe and Cu absorbed per 20 cm duodenal loop was similar for C and STZ rats. Zn, Fe and Cu absorption per gram dry mucosa were reduced 45-53% in STZ rats due to the 50% increase in mucosal mass. Morever, the quantity of radioisotopes accumulated per gram dry mucosa and the concentration of metallothionein per gram mucosal cytosol protein were similar in C and STZ animals. Together, these data demonstrate that increased absorption of dietary Zn and Cu is in part responsible for accumulation of these elements in STZ tissues and suggest altered metal transport at the luminal (brush border) surface of the intestinal epithelium.