Page 408 - Atlas of Histology with Functional Correlations

an endothelia cell (7) with organelles. Located in the center and completely

filling the capillary lumen is a section of a densely stained RBC (2) with its
characteristic biconcave shape (see Fig. 10.5 for comparison). Surrounding the
fenestrated endothelium (3) and the cytoplasm of the endothelial cell (7) is a
basal lamina (4, 6). Surrounding the capillary and the basal lamina (4, 6) are the
sections of the ependymal cell cytoplasm (1, 8) of the choroid plexus.

FIGURE 10.7 ■ Ultrastructure of a fenestrated capillary sectioned in the
transverse plane in the choroid plexus of a CNS ventricle. ×25,000.

FIGURE 10.8 | Muscular Artery and Vein

(Transverse Section)

The walls of blood vessels contain elastic tissue that allows them to expand and

contract. In this illustration, a muscular artery (1) and vein (4) have been cut in
the transverse plane and prepared with a plastic stain to illustrate the distribution
of elastic fibers in their walls. The elastic fibers stain black, and the collagen
fibers stain light yellow.

The wall of the artery (1) is thicker and contains more smooth muscle fibers
than the wall of the vein (4). The innermost layer tunica intima of the artery (1)
is stained dark because of the thick IEL (1a). The thick middle layer of the

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