Fig. 5.

Photomicrographs of spleen sections for the normal control (A), sub-acute (B–D) and sub-chronic (E–G) stage. (A) Control: normal tissue with the red and white pulps and the marginal zone separating them (B) Low dose: shows accumulation of hemosiderin (blue arrows) within the reticuloendothelial cells (blue arrows). (C) Medium dose: shows venous congestion (CN) with a little tissue distortion as compared to the control and low dose groups. (D) High dose: distortion of reticuloendothelial tissue and cytoarchitecture (black arrows) of spleen and atrophy of cells with marked spaces between adjacent immune cells. (E) Low dose: deposition of hemosiderin in the reticuloendothelial tissues. (F) Medium dose: shows sinusoidal dilatation and oedema (black arrows). (G) High dose: shows sinusoidal dilatation evident as oedema (black arrows), more severe than what is observed in the medium dose group (H & E × 40).