Shulman R J, Schanler R J, Lau C, Heitkemper M, Ou C N, Smith E O
USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA.
J Pediatr. 1998 Nov;133(5):645-9. doi: 10.1016/s0022-3476(98)70105-2.
We sought to ascertain whether the timing of feeding initiation affected the development of intestinal lactase activity and whether there are clinical ramifications of lower lactase activity.
Preterm infants (26 to 30 weeks' gestation; n = 135) were randomly assigned to begin enteral feedings at either 4 (early group) or 15 days of age (standard group). At 10, 28, and 50 days of age lactase activity was determined by measuring the urinary ratio of lactulose/lactose after the 2 sugars were administered.
Lactase activity increased significantly over time. Infants in the early group had greater lactase activity at 10 days of age (by 100%) and 28 days of age (by 60%) than the standard group. At 10 days of age lactase activity was greater in milk- versus formula-fed infants. The time required to achieve full enteral feedings, the number of abnormal abdominal x-ray examinations, and the total number of abdominal x-ray examinations were inversely related to lactase activity.
Early feeding increases intestinal lactase activity in preterm infants. Lactase activity is a marker of intestinal maturity and may influence clinical outcomes. Whether the effects of milk on lactase activity were due to the greater concentration of lactose in human milk compared with that in formula must be determined.
我们试图确定开始喂养的时间是否会影响肠道乳糖酶活性的发展，以及较低的乳糖酶活性是否存在临床后果。
将早产婴儿（孕龄26至30周；n = 135）随机分为两组，分别在4日龄（早期组）或15日龄（标准组）开始肠内喂养。在10日龄、28日龄和50日龄时，通过测量给予两种糖后尿中乳果糖/乳糖的比值来测定乳糖酶活性。
乳糖酶活性随时间显著增加。早期组婴儿在10日龄时（高出100%）和28日龄时（高出60%）的乳糖酶活性高于标准组。在10日龄时，母乳喂养婴儿的乳糖酶活性高于配方奶喂养婴儿。实现完全肠内喂养所需的时间、异常腹部X光检查的次数以及腹部X光检查的总数与乳糖酶活性呈负相关。
早期喂养可增加早产婴儿的肠道乳糖酶活性。乳糖酶活性是肠道成熟的一个标志，可能会影响临床结局。牛奶对乳糖酶活性的影响是否归因于人乳中乳糖浓度高于配方奶，这一点必须予以确定。
