Page 415 - Atlas of Histology with Functional Correlations

endocardium (9). The endocardium (9) extends over the pulmonary valve (6)

and the annulus fibrosus (8) and blends in with the tunica intima (5a) of the
pulmonary trunk (5).

The pulmonary trunk (5) is lined by the subepicardial connective tissue and
adipose tissue (2), which, in turn, is covered by the epicardium (1). Both of
these layers cover the external surface of the right ventricle. Coronary arterioles

and venules (3) are found in the subepicardial connective tissue (2).

FIGURE 10.13 ■ Heart: a section of the right ventricle, pulmonary trunk, and
pulmonary valve (longitudinal section). Stain: hematoxylin and eosin. Low
magnification.

FIGURE 10.14 | Heart: Contracting Cardiac

Muscle Fibers and Impulse-Conducting Purkinje

Fibers

This figure illustrates a section of the heart stained with Mallory-Azan stain. The
blue-stained collagen fibers accentuate the subendocardial connective tissue

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