AGE- AND EXPERIMENTAL FACTOR–INDUCED MORPHOMETRIC CHANGES IN LYMPH NODES: AN EXPERIMENTAL STUDY IN WHITE OUTBRED RATS
Keywords:
Lymph node; morphometry; histology; white outbred rat; immune system; lymphoid follicle; germinal center; paracortical zone; hyperplasia; involution.Abstract
This study evaluated age-related and experimentally induced morphological and morphometric alterations in the lymph nodes of 3-, 6-, and 12-month-old white outbred rats. Histological and morphometric analyses demonstrated preservation of the normal lymph node architecture in the control groups, whereas physiological involution progressively developed with age. In the experimental groups, young (3- and 6-month-old) animals exhibited marked lymphoid hyperplasia characterized by enlarged lymphoid follicles, expanded germinal centers, and increased cellular density within the paracortical region. In contrast, 12-month-old rats showed a combination of hyperplastic responses and age-associated involutional remodeling. The findings indicate that aging and experimental exposure exert distinct but interacting effects on lymph node structure and function, providing new insights into adaptive remodeling of peripheral lymphoid organs.
References
1.Normal lymph node architecture was maintained in control animals despite age-related involution.
2. Experimental exposure stimulated lymphoid hyperplasia in young rats.
3.The strongest adaptive response was observed in 6-month-old animals.
4.Older rats exhibited combined hyperplastic and involutional changes.
5.Morphometric parameters reliably reflected age- and exposure-dependent remodeling of lymph nodes.
