Ivan M
Br J Nutr. 1987 May;57(3):479-88. doi: 10.1079/bjn19870055.
The absorption and secretion of 65Zn in the stomach and intestinal tract regions was studied in sets of two and three sheep which were exchanging digesta via re-entrant cannulas in the proximal duodenum. One sheep from each of the three three-sheep sets was dosed intraruminally with the radioisotope. One sheep from the three two-sheep sets received an intravenous dose. Measurements of 65Zn in blood plasma from intraruminally dosed sheep showed that there was no apparent absorption from the stomach region. Measurements from sheep receiving radioactive digesta intraduodenally showed that mean apparent absorption of 65Zn was 0.07 and mean true absorption was 0.103. There was a large variation in endogenous recycling of 65Zn into the stomach region. Secretion of 65Zn into the stomach and intestinal regions in the intravenously dosed sheep of the two-sheep sets was calculated on the basis of total recovery over 10 d in the digesta and faeces. The present study showed that for every 1 molecule Zn secreted into the stomach region, 2.1 molecules were secreted into the intestinal tract region.
通过在近端十二指肠使用折返式套管使两组和三组绵羊相互交换食糜，研究了胃肠道区域中65Zn的吸收和分泌情况。在每组三只绵羊中，有一只绵羊经瘤胃内给予放射性同位素。在每组两只绵羊中，有一只绵羊接受静脉注射剂量。对经瘤胃内给药的绵羊血浆中的65Zn进行测量，结果表明胃区域没有明显的吸收。对经十二指肠内给予放射性食糜的绵羊进行测量，结果表明65Zn的平均表观吸收率为0.07，平均真实吸收率为0.103。65Zn向胃区域的内源性再循环存在很大差异。根据两组两只绵羊经静脉给药后，食糜和粪便中10天内的总回收率，计算了65Zn向胃和肠道区域的分泌量。本研究表明，每分泌1个锌分子到胃区域，就有2.1个分子分泌到肠道区域。
