Structural and functional characteristic of the nervous and endocrine systems and the microbiota composition in the colon of the newborn and prepubescent wistar rats

The aim was to characterize the structural and functional features of the nervous and endocrine systems and the microbiota composition of the colon in newborns and prepubescent Wistar rats. Materials and methods: The study was performed on 12 newborns and 13 prepubescent male Wistar rats. We used immunohistochemical methods to investigate the structure of the intermuscular nerve plexus and to detect endocrine cells in the colon. The concentration of serotonin in the colon wall and peripheral blood plasma was evaluated with high-performance liquid chromatography. The ratio of the main taxa of bacteria of the luminal microbiota was determined by real-time PCR. Results: We identified that in the neonatal period the intermuscular nerve plexus was not completely formed, there were few glial cells in the ganglia. The relative number of enteroendocrine cells and the serotonin content in the intestinal wall and in blood at this age period was minimal. The composition of the luminal microbiota in newborn rats was characterized by the predominance of taxons Firmicutes, Enterobacteria. In comparison with the newborns the intermuscular nerve plexus in the prepubescent rats was mature: the neural network formed large mesh, while the number of glial cells in the ganglia increased 3-4 times. The number of enteroendocrine cells increased 2.5 times, the content of serotonin in the colon wall and peripheral blood increased almost 80 and 6000 times, respectively. Firmicutes predominated in the luminal microflora, the number of Bifidobacteria, Enterobacteria decreased.

ободочная кишка, крысы, новорожденные, препубертатные, энтеральная нервная система, энтероэндокринные клетки, серотонин, микрофлора, colon, rat, newborn, prepubescent, enteric nervous system, enteroendocrine cells, serotonin, microflora