COMPARATIVE CHARACTERISTIC OF MORPHOMETRIC PARAMETERS OF GERMINAL CENTERS IN THE AGGREGATED LYMPHOID NODULES OF THE SMALL INTESTINE AND MESENTERIC LYMPH NODES FOLLOWING ACUTE EMOTIONAL STRESS

Under physiological conditions, the germinal center (GC) area of aggregated lymphoid nodules of the small intestine in adult male Wistar rats was greater than that of the similar structures in the mesenteric lymph nodes. Moreover, these differences were more pronounced in a group of stress-resistant rats as compared to stress-prone animals. The exposure to acute emotional stress (immobilization in plexiglas boxes for 1 hour with the irritation of the back area with the electric current) reduced GC size. Restoration of the morphometric parameters studied in the group of stress-resistant rats was completed at an earlier date (by Day 3 after exposure to stress), while in susceptible animals it took place by Day 7. By Day 14 after an acute emotional stress, GC size in a group of stress-resistant rats were similar to those in control group, while in susceptible animals they were lower than the baseline values, indicating that the depletion of the functional capacities of lymphoid tissue in this group of animals.

aggregated lymphoid nodules, mesenteric lymph nodes, germinal centers, acute emotional stress, Wistar rats