Structural changes of Peyer’s patches of male rat Wistar during postnatal ontogenesis
In the whole mounts of small intestine from 32 male Wistar rats of different age groups a quantitative assessment was conducted, and in histological slices - qualitative assessment of the Peyer’s patches. The total area of the small intestine, length, number of plaques and the number of lymphoid nodules in them were determined. In compare with 4-6 week rats the length of the small intestine of 5-6 days ones is increased by 2.8 times and in subsequent periods of postnatal development, it is not changed. According to the quantitative evaluation of the Peyer’s patches, and lymph nodules in them, the number of Peyer’s patches in the wall of the jejunum and ileum at 5-6 days old rats is 7.0, and lymphoid nodules in them is 6.6. At the age of 4-6 weeks up to the 2-3 months these figures are increased by 3 times. Total plaque number is not changed at the age of 13-14 months, but the number of lymphoid nodules, compared with the previous period, is increased by 1.3 times. Plaques per unit and the number of spare nodules are increased in the ileum compared with the jejunum at the age of 5-6 days. The number of nodules in it reaches a maximum at the age of 2-3 months, and in 13-14 months - is decreased. Dynamics of the average area of plaques is similar, but readings are maximal in the age of 13-14 months.