Page 446 - Atlas of Histology with Functional Correlations

This low-power photomicrograph illustrates the lymph node cortex and medulla.

A loose connective tissue capsule (4) with blood vessels and adipose cells (7)
covers the lymph node. Inferior to the capsule (4) is the subcapsular (marginal)
sinus (5), which overlies the darker-staining and peripheral lymph node cortex
(3). The cortex (3) exhibits numerous lymphatic nodules (1, 6), some with a
lighter-staining germinal center (2).

The central region of the lymph node is the lighter-staining medulla (9),
characterized by the dark-staining medullary cords (12) and the light-staining
lymphatic channels, the medullary sinuses (11). The medullary sinuses (11)
drain the lymph that enters the lymph node through the afferent lymphatic

vessels in the capsule (see Fig. 11.5) and converges toward the hilum of the
lymph node (see Fig. 11.2) that contains numerous arteries (8) and veins. The
lymph leaves the lymph node via the efferent lymphatic vessels with valves
(10) at the hilum.

FIGURE 11.6 ■ Cortex and medulla of a lymph node. Stain: Mallory-Azan.
×25.

FIGURE 11.7 | Lymph Node: Subcortical Sinus

and Lymphatic Nodule

This figure illustrates, at a higher magnification and in greater detail, a portion of
the lymph node with the connective tissue capsule (3), trabecula (4), and
subcapsular sinus (1) that continue on both sides of the trabecula (4) as

trabecular sinuses (12) into the interior of the lymph node.

The reticular connective tissue, the reticular cells (8, 11), is seen in different

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