Wapnir R A, Garcia-Aranda J A, Mevorach D E, Lifshitz F
J Nutr. 1985 Jul;115(7):900-8. doi: 10.1093/jn/115.7.900.
The differences in zinc absorption in the presence of four low-molecular-weight ligands in the jejunum, ileum and colon of protein-energy malnourished juvenile rats (M), and their controls (C) were investigated. An in vivo perfusion procedure was applied to vascularly intact segments of the three areas of the gut. The absorption of L-proline and L-histidine, and a hydrolysis-resistant dipeptide, glycylsarcosine, were also determined. In certain instances, the M rats absorbed zinc at a lower rate than the C animals. This effect was especially consistent throughout the gut when glycylsarcosine was present in the perfusates. In the colon, zinc, but not the amino acids, was taken up. Glycylsarcosine was well absorbed by the colon in both the M and C rats. The data indicate that protein-energy deficiency may impair the absorption of zinc by the rat intestinal mucosa in the presence of low-molecular-weight substances of high affinity for zinc, without altering the absorption of amino acids, or of zinc organometallic complexes in which the metal is tightly bound. The two contrasting situations may be relevant to alleviating zinc deficiency in nutritionally compromised conditions.
研究了蛋白质 - 能量营养不良的幼年大鼠（M组）及其对照组（C组）空肠、回肠和结肠中存在四种低分子量配体时锌吸收的差异。采用体内灌注法对肠道三个区域的完整血管段进行研究。还测定了L - 脯氨酸、L - 组氨酸以及一种抗水解二肽甘氨酰肌氨酸的吸收情况。在某些情况下，M组大鼠锌的吸收速率低于C组动物。当灌注液中存在甘氨酰肌氨酸时，这种效应在整个肠道中尤为一致。在结肠中，锌被吸收，但氨基酸未被吸收。甘氨酰肌氨酸在M组和C组大鼠的结肠中均被良好吸收。数据表明，在存在对锌具有高亲和力的低分子量物质的情况下，蛋白质 - 能量缺乏可能会损害大鼠肠黏膜对锌的吸收，而不会改变氨基酸或金属紧密结合的有机金属锌络合物的吸收。这两种截然不同的情况可能与在营养受损条件下缓解锌缺乏有关。
