Weström B, Svendsen J, Tagesson C
Gut. 1984 May;25(5):520-5. doi: 10.1136/gut.25.5.520.
The intestinal permeability of different sized molecules in the neonatal pig was investigated. Piglets of varying age (0-168 h) were given a mixture of different sized polyethyleneglycols (414-942 dalton polyethyleneglycols) together with ovalbumin and bovine serum albumin by stomach tube, and the serum concentrations were determined two hours after feeding. Considerable amounts of ovalbumin and bovine serum albumin were found in the serum of animals up to 24 hours of age, whereas very little or none at all was found in sera from older animals. By contrast, an intestinal permeability barrier to polyethyleneglycols in the 414-942 dalton range was found not only in the older animals but in all pigs investigated, including the newborn, unsuckled. In addition, the permeability barrier to polyethyleneglycols was found in a pig which was starved to prevent macromolecular closure and, therefore, absorbed considerable amounts of bovine serum albumin and ovalbumin. These findings indicate that 414-942 dalton polyethyleneglycols cross the intestinal mucosa at different rates due to size regardless of age of the animals and regardless of whether the mucosa is permeable to protein or not. This suggests that low molecular weight molecules like 414-942 dalton polyethyleneglycols and macromolecules (proteins) cross the neonatal gut wall through different routes.
研究了新生仔猪对不同大小分子的肠道通透性。给不同年龄（0 - 168小时）的仔猪经胃管投喂不同大小的聚乙二醇（414 - 942道尔顿的聚乙二醇）与卵清蛋白和牛血清白蛋白的混合物，并在喂食两小时后测定血清浓度。在24小时龄以内的动物血清中发现了大量的卵清蛋白和牛血清白蛋白，而在年龄较大动物的血清中发现的量很少或根本没有。相比之下，不仅在年龄较大的动物中，而且在所有被研究的猪（包括新生未哺乳的仔猪）中都发现了对414 - 942道尔顿范围内聚乙二醇的肠道通透性屏障。此外，在一头为防止大分子封闭而饥饿的猪中也发现了对聚乙二醇的通透性屏障，因此该猪吸收了大量的牛血清白蛋白和卵清蛋白。这些发现表明，414 - 942道尔顿的聚乙二醇由于大小不同，无论动物年龄以及黏膜是否对蛋白质通透，均以不同速率穿过肠黏膜。这表明像414 - 942道尔顿聚乙二醇这样的低分子量分子和大分子（蛋白质）通过不同途径穿过新生仔猪的肠壁。
