Kaouass M, Deloyer P, Wery I, Dandrifosse G
Department of Biochemistry, University of Liege, Belgium.
Dig Dis Sci. 1996 Jul;41(7):1434-44. doi: 10.1007/BF02088570.
In the present investigation, we analyzed the mechanism involved in spermine-induced intestinal maturation in suckling rats. Spermine was given orally to suckling pups and biochemical as well as morphological parameters were studied at different times after the beginning of the treatment. Eight hours after administration, spermine produced cell elimination at the villus tops and a decrease in intestinal DNA and protein content. In parallel, protein and DNA concentration and disaccharidase activity were enhanced in the chyme. These transitory alterations were not induced by growth inhibition, as DNA synthesis was not modified, although a brief decrease in protein synthesis was observed. Spermine was not metabolized in cytotoxic products: rat pretreatment with MDL72527 (an inhibitor of polyamine oxidase) did not avoid the decrease in disaccharidase activity and in DNA and protein content. Three days after treatment, sucrase and maltase activity was higher in rats treated with spermine and MDL72527 than that in animals receiving spermine alone. Lactulose or acetylspermine ingestion induced intestinal maturation. Our data suggest that dietary polyamines exert a direct and specific maturational effect on rat small intestine and that an early decrease in lactase activity plays an important role in this phenomenon.
在本研究中，我们分析了精胺诱导乳鼠肠道成熟的机制。给乳鼠口服精胺，并在治疗开始后的不同时间研究生化和形态学参数。给药8小时后，精胺导致绒毛顶端细胞消除，肠道DNA和蛋白质含量降低。同时，食糜中的蛋白质和DNA浓度以及双糖酶活性增强。这些短暂的变化并非由生长抑制引起，因为DNA合成未改变，尽管观察到蛋白质合成有短暂下降。精胺不会代谢为细胞毒性产物：用MDL72527（一种多胺氧化酶抑制剂）预处理大鼠并不能避免双糖酶活性以及DNA和蛋白质含量的降低。治疗三天后，用精胺和MDL72527处理的大鼠的蔗糖酶和麦芽糖酶活性高于仅接受精胺处理的动物。摄入乳果糖或乙酰精胺可诱导肠道成熟。我们的数据表明，膳食多胺对大鼠小肠具有直接且特定的成熟作用，并且乳糖酶活性的早期降低在这一现象中起重要作用。
