Histochemical evaluation of mucins distribution of the gastroesophageal zone esophageal epithelium in the embryonal and fetal periods of human ontogenesis (part I)

Abstract

To study the quantitative and qualitative mucins profile of gastroesophageal zone (GEZ) epithelium during stages of the embryonal and fetal ontogenesis periods we have performed morphometrical and histochemical researches of the gastroesophageal junction (GEJ) epithelial differon. The current study was carried out on 169 human embryos and fetuses of gestational age from 4–5 till 38 weeks. It was established that during early embryonal period (5–6 weeks) gradual increase of neutral and acid mucins in esophageal part of the GEJ epithelial differon is observed. For early fetal period (10–28 weeks) disappearance of acid syalomucins in the GEJ enterocytes from 10 till 18 week and increasing of neutral mucin till 7,65±0,18% with falling of its level in 18–20 weeks period and decreasing till 2,4±0,10% in 28 weeks (р<0,001) was typical. Late fetal period from 28 till 38 weeks is characterized by complete structural rearrangement of epithelial differon of the GEZ stratified squamous nonkeratinized epithelium with formation of two functional zones: protective germinative in esophageal part of GEJ with incomplete histochemical cytodifferentiation of the GEJ esophageal epithelium. It was proved by remains of acid mucins (syalomucins) which are untypical for mature esophageal epithelium. Thus, the obtained data on the histological features of the GEZ epithelial differon in the prenatal period of ontogenesis will improve the accuracy of diagnosis and assessment of pathological changes in the mucous membrane of the GEJ.