Page 407 - Atlas of Histology with Functional Correlations

of the endothelial cell (3), and the section of the pericyte process (5) are

surrounded by a basal lamina (2, 7). Adjacent to the capillary wall is a section
of a myelinated axon (8) and a dense meshwork of fibers from axons, dendrites,
and astrocytic endfeet of glial cells. This neural meshwork that fills the spaces in
the CNS is called neuropil (1, 4).

FIGURE 10.6 ■ Ultrastructure of a continuous capillary sectioned in the
transverse plane in the CNS. Courtesy of Dr. Mark DeSantis, Professor
Emeritus, WWAMI medical Program, University of Idaho, Moscow, ID.

×25,000.

FIGURE 10.7 | Ultrastructure of Fenestrated

Capillary Sectioned in Transverse Plane in

Choroid Plexus of CNS Ventricle

The ultrastructure of a fenestrated capillary exhibits a different type of

endothelium that is seen in a continuous capillary (see Fig. 10.6). This capillary
endothelium (3) exhibits numerous opening or fenestrations (arrows) (3)
around the entire periphery of the capillary lumen (5) that are closed by thin
diaphragms (arrows) (3). On the right side of the capillary is the cytoplasm of

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