Koldovský O, Bedrick A, Thornburg W
Endocrinol Exp. 1986 Aug;20(2-3):119-30.
Colostrum and milk contain insulin, epidermal growth factor and prostaglandins. Experiments performed in our laboratory have demonstrated that these three substances can be absorbed by the gastrointestinal tract of suckling rats in biologically active form in considerable amounts. Prostaglandins are metabolized by the gastrointestinal tract during postnatal development. There are quantitative and qualitative differences in the metabolism of orally administered prostaglandins between suckling and weanling rats. Nevertheless, a significant amount of intact prostaglandin appears in the liver of suckling rats after oral administration. Gastric administered insulin can result in hypoglycemia. In suckling rats, there is a considerable decrease in blood glucose levels, while no effect is seen in 30-day-old rats. Epidermal growth factor is processed in the gastrointestinal tract as shown by size exclusion and affinity columns and surface receptor binding. Oral administration of epidermal growth factor has several effects on gastrointestinal functions. Analysis of epidermal growth factor processing by the gastrointestinal tract demonstrated postnatal developmental differences (either during normal development, or one accelerated by steroid treatment). These studies show that the gastrointestinal tract can be influenced by orally administered hormones known to be present in milk, and that these substances can be delivered to peripheral organs of suckling animals intact.
初乳和乳汁中含有胰岛素、表皮生长因子和前列腺素。我们实验室进行的实验表明，这三种物质能以生物活性形式被哺乳大鼠的胃肠道大量吸收。前列腺素在出生后的发育过程中会被胃肠道代谢。哺乳大鼠和断奶大鼠口服前列腺素后的代谢存在量和质的差异。然而，口服后，相当数量的完整前列腺素会出现在哺乳大鼠的肝脏中。胃内注射胰岛素会导致低血糖。在哺乳大鼠中，血糖水平会显著下降，而在30日龄大鼠中则没有效果。通过尺寸排阻柱、亲和柱和表面受体结合表明，表皮生长因子在胃肠道中会被加工处理。口服表皮生长因子对胃肠功能有多种影响。对胃肠道加工处理表皮生长因子的分析表明存在出生后发育差异（无论是在正常发育过程中，还是在类固醇治疗加速发育的过程中）。这些研究表明，胃肠道会受到口服已知存在于乳汁中的激素的影响，并且这些物质能够完整地输送到哺乳动物的外周器官。
