Spleen Slides

Histology: The exterior surface of the spleen consists of a capsule containing collagen and elastic fibers; the interior components are collectively called the "pulp". Upon gross examinagtion of a slice of the spleen, the pulp has two very different appearances: red and white. The organ appears as a large expanse of red pulp dotted with white pulp. Histologically,red pulp is "red" due to the presence of large numbers of erythrocytes in blood vessels called sinuses and white pulp is "white" due to lack of these sinuses and consequently fewer erythrocytes. The red pulp surrounds the white pulp while the latter looks like lymphatic nodules. Closer inspection of the white pulp indicates that there is a "central arteriole", sometimes called a central artery, close to the center of each area of white pulp.

Micrographs of dog spleen . (Lab slide 30)