General morphological characteristics of gastro-intestinal tract of rats with experimental undifferentiated dysplasia of connective tissue

Abstract

The main purpose of the study is to determine peculiar morphological characteristics of structural changes of alimentary system organs in the case of experimental undifferentiated dysplasia of connective tissue (UDCT). Intranatal antigen introduction was conducted as an experimental model of UDCT. Objects of investigation – pharynx, duodenum, ileum, caecum, ascendant colon of white rats from the first up to the 60th day of postnatal life. Animals were contained in standard conditions of vivarium according to Law of Ukraine № 1759-VI (15.12.2009) On the Protection of Animals from Cruelty. Morphological structure of organs were examined at days 1st, 7th, 14th, 21th, 45th, 60th after birth. Morphometric, histological, histochemical, lectinistochemical, immunehistochemic and statistic methods were used. Analysis of the obtained results was conducted by means of statistical methods with the use of computer license program «Statistica for Windows 13» (StatSoft Inc., № JPZ804I382130ARCN10-J). The compared results considered such, that for certain differ at р<0,05, that is generally accepted for biological and medical researches. On the background of experimental syndrome of UDCT, developed by intranatal antigen loading, it is settled that the number of intraepithelial lymphocytes, number of lymphocytes of submucose layer of alimentary tract increases. Ratio between cells of mucosa (including epithelial layer and submucosal layer) changes. Interrelation between layers of alimentary tube changes resulting in the thickening of mucosa (including epithelial layer and submucosal layer) and thinning of muscular layer. These inflections result in elongation of duodenum, small and large intestines. Throughout the first month after birth in rats with experimental syndrome of UDCT lymphocyte/epitheliocyte, lymphocyte/ fibroblast and lymphocyte/mitosis indexes change in proximal and distal parts of digestive tract.