The features of lymph-node reaction to tissue damage in the lymph-drainage area in elderly rats

Resumo

Light microscopy has been used to study the reaction of submandibular lymph nodes (LNs) to surgical damage to the tissues of the maxillofacial region in elderly rats. Connective tissue was more abundant in the LNs of elderly rats than in those of mature animals, regardless of the time of observation (even before surgery). Moreover, the duration of the changes of the volume of the cortical plateau was increased in the old rats, whereas the duration of the changes in paracortex and lymphoid nodules devoid of germinal centers was reduced. The distinctive cytoarchitectonic features included a significant reduction of the number of lymphocytes, mitotic figures, and immuno- and plasmablasts concomitant with the elevation of the number of macrophages, cellular elements that showed signs of destruction, reticulocytes, and red blood cells.