Department of Maternal and Child Health, Faculty of Public Health, Sun Yat-sen University, Guangzhou, China.
Comparative Pediatrics and Nutrition, Department of Veterinary and Animal Sciences, University of Copenhagen, Copenhagen, Denmark.
Dev Neurosci. 2019;41(3-4):247-254. doi: 10.1159/000505726. Epub 2020 Feb 3.
Preterm birth is associated with impaired brain functions, but it is unknown whether fetal growth restriction (GR) makes these deficits worse. Using piglets as a model for preterm infants, we hypothesized that moderate GR reduces growth rate, physical activity, and spatial memory in the first weeks after preterm birth.
Preterm pigs were delivered by caesarean section and fed until 19 days (n = 830 from 55 pregnant sows) and received intensive clinical care. GR pigs were classified as animals with the lowest 5-20% percentile birth weight within each litter and were compared with litter-mate controls (21-100% percentile birth weight). Basic motor skill development, physical activity, and morbidities (e.g., necrotizing enterocolitis) were recorded within the first week. Weight of internal organs and data from a T-maze spatial memory test were noted until 19 days.
Moderate GR and control preterm pigs (birth weights 728 ± 140 and 1,019 ± 204 g, respectively) showed similar relative weights of internal organs (relative to body), except higher adrenal gland weights in GR pigs (+20-50%, p < 0.05). This was associated with a tendency to higher plasma cortisol (p < 0.05 on day 11). GR preterm pigs showed delayed ability to stand and walk (days 2-5, p < 0.01), but physical activity and proportion of correct choices in a T-maze test (70.3 vs. 71.6%) were similar.
Moderate GR has limited effect on motor function and spatial memory in the early postnatal period of preterm pigs, despite some initial delays in basic motor skills. In the postnatal period, moderately growth-restricted preterm infants may adapt well with regards to organ growth and neurodevelopment.
早产与脑功能受损有关，但目前尚不清楚胎儿生长受限（GR）是否会使这些缺陷更加严重。我们使用小猪作为早产儿模型，假设中度 GR 会降低早产儿出生后第一周的生长速度、身体活动和空间记忆。
通过剖腹产分娩早产儿，并喂养至 19 天（来自 55 只怀孕母猪的 830 只），并接受强化临床护理。GR 猪被归类为每个窝中出生体重最低的 5-20%百分位的动物，并与同窝对照（21-100%百分位出生体重）进行比较。在第一周内记录基本运动技能发展、身体活动和发病率（例如坏死性小肠结肠炎）。在 19 天内记录内脏器官的重量和 T 迷宫空间记忆测试的数据。
中度 GR 和对照早产儿猪（出生体重分别为 728±140 和 1019±204 克）的内脏器官相对重量（相对于体重）相似，但 GR 猪的肾上腺重量较高（+20-50%，p<0.05）。这与血浆皮质醇水平升高的趋势有关（第 11 天 p<0.05）。GR 早产儿猪站立和行走的能力延迟（第 2-5 天，p<0.01），但身体活动和 T 迷宫测试中的正确选择比例（70.3%比 71.6%）相似。
尽管基本运动技能最初存在一些延迟，但中度 GR 对早产仔猪出生后早期的运动功能和空间记忆影响有限。在出生后时期，中度生长受限的早产儿可能在器官生长和神经发育方面适应良好。
