Figure 4

Photomicrograph of popliteal lymph nodes. (a & b) The popliteal lymph nodes from a control rat show severe degeneration with a mild necrotic area (N) and a slight increase in the number of lymphocytes (arrow). (c & d) The popliteal lymph nodes from a rat belonging to the Sa30 group showed lymphoid follicles (f) with germinal centers and a slight increase in the number of lymphocytes (arrow). (e & f) The popliteal lymph nodes of a rat belonging to the Sa50 group showed parafollicular hyperplasia (f) and a slight increase in the number of lymphocytes (arrow) (H&E stain, ×5 and ×10 magnification).