Karnak I, Tanyel F C, Müftüoğlu S, Unsal I, Cakar N, Büyükpamukçu N, Hiçsönmez A
Department of Pediatric Surgery, Hacettepe University, Faculty of Medicine, Ankara, Turkey.
Eur J Pediatr Surg. 1996 Dec;6(6):328-33. doi: 10.1055/s-2008-1071008.
The role of amniotic fluid ingestion on the development of various fetal organic systems was evaluated in the rabbit model. The fetuses from 24 New Zealand white rabbits were studied on the 23rd day of gestation. Right ovarian-end fetuses underwent esophageal ligation (EL) or sham (SH) operations. Rabbits were submitted to hysterectomy on gestational day 30, and various organic systems of live fetuses were examined by weight and histological evaluations. Additionally, small intestinal enzymes were determined. Three fetal deaths, one in EL and two in SH groups, occurred with a total survival rate of 85%. EL resulted in increased amniotic fluid volume. Although fetal body weights (BW), lung, heart, liver and renal weights and liver weight/BW, lung weight/BW ratios did not differ, gastric, small intestinal and total gastrointestinal tract weights significantly decreased in EL group (p < 0.05). Additionally, gastric weight/BW, small intestinal weight/BW, total gastrointestinal tract weight/BW and renal weight/BW ratios were also significantly decreased (p < 0.01). Sucrase and maltase activities were not detectable in either group. Lactase activity in proximal small intestinal tissue was significantly decreased in EL group (p < 0.05). Mid and distal small intestinal tissue lactase activities did not reveal any significant difference among groups. Histologically, alveolar enlargement and alveolar thickening in fetal lungs, decreased glomerular count and tubular degeneration in fetal kidneys, and slight changes in fetal livers such as cellular vacuolization and reduction in central vein count were observed in the fetuses with esophageal ligation. While small intestinal tissues showed no marked changes, fetal stomach tissues in EL group revealed marked histological alterations consistent with erosive gastritis. This study suggests that amniotic fluid ingestion has no important effects on fetal somatic growth but effects the development of various fetal organic systems. Since the nutritional role of amniotic fluid is obscure, changes in amniotic fluid dynamics, and/or impairment of release of some possible fetal organotrophic factors, and/or unused states of the organs may be responsible for the morphologic changes secondary to esophageal ligation.
在兔模型中评估了羊水摄入对胎儿各器官系统发育的作用。选取24只新西兰白兔的胎儿，在妊娠第23天进行研究。右侧卵巢端胎儿接受食管结扎（EL）或假手术（SH）。在妊娠第30天对兔子进行子宫切除术，通过重量和组织学评估检查存活胎儿的各种器官系统。此外，还测定了小肠酶。发生3例胎儿死亡，EL组1例，SH组2例，总存活率为85%。EL导致羊水量增加。虽然胎儿体重（BW）、肺、心脏、肝脏和肾脏重量以及肝脏重量/BW、肺重量/BW比值无差异，但EL组胃、小肠和全胃肠道重量显著降低（p<0.05）。此外，胃重量/BW、小肠重量/BW、全胃肠道重量/BW和肾脏重量/BW比值也显著降低（p<0.01）。两组均未检测到蔗糖酶和麦芽糖酶活性。EL组近端小肠组织乳糖酶活性显著降低（p<0.05）。中、远端小肠组织乳糖酶活性在各组间无显著差异。组织学上，食管结扎的胎儿出现肺泡增大和肺泡增厚、肾小球数量减少和肾小管变性，胎儿肝脏出现细胞空泡化和中央静脉数量减少等轻微变化。小肠组织无明显变化，而EL组胎儿胃组织出现与糜烂性胃炎一致的明显组织学改变。本研究表明，羊水摄入对胎儿体细胞生长无重要影响，但影响胎儿各器官系统的发育。由于羊水的营养作用尚不清楚，羊水动力学的改变和/或某些可能的胎儿器官营养因子释放受损和/或器官的未使用状态可能是食管结扎继发形态学改变的原因。
