Nuñez M C, Ayudarte M V, Morales D, Suarez M D, Gil A
UNIASA, Departamento, de Investigación, Granada, Spain.
JPEN J Parenter Enteral Nutr. 1990 Nov-Dec;14(6):598-604. doi: 10.1177/0148607190014006598.
Nucleic acid synthesis in tissues of rapid growth is preferentially done using dietary purines and pyrimidines via the salvage pathway. In the case of a low protein intake, dietary nucleotides may be semiessential for cell replication of gut, lymphocytes, and bone marrow, and especially in those intestinal diseases in which the mucosa is altered, dietary nucleotides may have a role in intestinal development. The effect of dietary nucleotides on intestinal weight and length, gut mucosal weight, intestinal protein and DNA contents, and lactase, maltase, and intestinal mucosal activities was assessed in a controlled way. Weanling (21-day-old) rats were separated into two groups of 36, each receiving blindly a basal diet containing glucose polymers (C) or a basal diet with lactose as the main carbohydrate (L) for 15 days. Those fed with L developed a syndrome of chronic diarrhea and malnutrition. Ten rats of each group were sacrificed at that time. The rest of the animals of each group were separated into two subgroups. The first was fed with the C diet and the second with the C diet supplemented with 50 mg/100 g of each of the following nucleotides: AMP, GMP, CMP, UMP, and IMP (CN). Thus the subgroups CC, CN, LC, and LN were formed. Rats were sacrificed after 4 weeks and gut separated into three segments corresponding to duodenum, jejunum, and ileum. Analysis of variance was used to compare the effect of diet or segments. DNA and lactase, maltase, and sucrase activities increased in the LN group with respect to LC especially in jejunum and ileum but there were not any differences between CC and CN.(ABSTRACT TRUNCATED AT 250 WORDS)
快速生长组织中的核酸合成优先通过补救途径利用膳食嘌呤和嘧啶来完成。在蛋白质摄入量较低的情况下,膳食核苷酸对于肠道、淋巴细胞和骨髓的细胞复制可能是半必需的,尤其是在那些黏膜发生改变的肠道疾病中,膳食核苷酸可能在肠道发育中发挥作用。以可控方式评估了膳食核苷酸对肠道重量和长度、肠黏膜重量、肠道蛋白质和DNA含量以及乳糖酶、麦芽糖酶和肠黏膜活性的影响。将断奶(21日龄)大鼠分为两组,每组36只,每组大鼠随机接受含葡萄糖聚合物的基础日粮(C组)或含乳糖作为主要碳水化合物的基础日粮(L组),持续15天。喂食L组日粮的大鼠出现了慢性腹泻和营养不良综合征。此时每组处死10只大鼠。每组其余动物再分为两个亚组。第一个亚组喂食C组日粮,第二个亚组喂食添加了以下每种核苷酸50 mg/100 g的C组日粮:AMP、GMP、CMP、UMP和IMP(CN组)。由此形成了CC、CN、LC和LN亚组。4周后处死大鼠,将肠道分为对应十二指肠、空肠和回肠的三段。采用方差分析比较日粮或肠段的影响。与LC组相比,LN组的DNA以及乳糖酶、麦芽糖酶和蔗糖酶活性增加,尤其是在空肠和回肠,但CC组和CN组之间没有差异。(摘要截取自250词)