The red pulp of rat spleen was examined by using electron microscope, which revealed that it was formed of a network of tortuous, branched venous sinuses separated from each other by the splenic (Bilfroth) cords. The cords were formed of spongy network of reticulum and cytoplasmic prolongations of reticulum cells and macrophages. The splenic venous sinus had three layers: an inner layer of endothelial cells, a middle layer of interrupted bsement membrane formed of reliculum and an outer layar of parasinusoidal cells (reticulum cells and macrophages). The differences between these three reticuloendothelial cells were also described. |
