Department of Biochemistry, Memorial University of Newfoundland, St John's, Newfoundland and Labrador, Canada.
JPEN J Parenter Enteral Nutr. 2012 Mar;36(2):205-12. doi: 10.1177/0148607111417447. Epub 2011 Dec 21.
Successful small intestinal (SI) adaptation following surgical resection is essential for optimizing newborn growth and development, but the potential for adaptation is unknown. The authors developed an SI resection model in neonatal piglets supported by intravenous and enteral nutrition.
Piglets (n = 33, 12-13 days old) were randomized to 80% SI resection with parenteral nutrition feeding (R-PN), 80% SI resection with PN + enteral feeding (R-EN), or sham SI transection with PN + enteral feeding (sham-EN). In resected pigs, the distal 100 cm of ileum (residual SI) and 30 cm of proximal SI were left intact. All pigs received parenteral nutrition postsurgery. Enteral nutrition piglets received continuous gastric infusion of elemental diet from day 3 (40:60 parenteral nutrition:enteral nutrition). Piglets were killed 4, 6, or 10 days postsurgery.
By 10 days, R-EN piglets had longer residual SI than R-PN and sham-EN pigs (P < .05). At days 6 and 10, R-EN piglets had greater weight per length of intact SI (P < .05) and isolated mucosa (P < .05) compared to other groups. Greater gut weight in R-EN piglets was facilitated by a greater cellular proliferation index (P < .01) by 4 days compared to other groups and greater overall ornithine decarboxylase activity vs R-PN piglets (P < .05).
This new model demonstrated profound SI adaptation, initiated early postsurgery by polyamine synthesis and crypt cell proliferation and only in response to enteral feeding. These changes translated to greater gut mass and length within days, likely improving functional capacity long term.
手术切除后的小肠(SI)成功适应对于优化新生儿的生长和发育至关重要,但适应的潜力尚不清楚。作者在接受静脉和肠内营养支持的新生仔猪中开发了一种 SI 切除术模型。
仔猪(n=33,12-13 天大)随机分为 80%SI 切除术+肠外营养喂养(R-PN)、80%SI 切除术+PN+肠内喂养(R-EN)或假手术+PN+肠内喂养(sham-EN)组。在接受切除术的猪中,保留了远端 100cm 的回肠(残留 SI)和 30cm 的近端 SI。所有猪术后均接受肠外营养。接受肠内营养的仔猪术后第 3 天开始接受要素饮食持续胃内输注(40:60 肠外营养:肠内营养)。术后第 4、6 和 10 天处死猪。
到第 10 天,R-EN 仔猪的残留 SI 比 R-PN 和 sham-EN 仔猪长(P<0.05)。在第 6 和 10 天,与其他组相比,R-EN 仔猪的完整 SI 长度和分离黏膜的重量/长度更大(P<0.05)。与其他组相比,R-EN 仔猪在第 4 天的肠细胞增殖指数(P<0.01)更高,整体鸟氨酸脱羧酶活性也更高,从而导致 R-EN 仔猪的肠道重量更大(P<0.05)。
这个新模型展示了深刻的 SI 适应,术后早期通过多胺合成和隐窝细胞增殖启动,仅对肠内喂养有反应。这些变化在数天内转化为更大的肠道质量和长度,可能长期改善其功能能力。