Page 900 - Atlas of Histology with Functional Correlations

taller epithelium.

Surrounding the alveoli are the myoepithelial cells (8) present between the

alveolar cells and the basal lamina. With certain planes of section, the
myoepithelial cells (8, upper leader) surround the secretory alveoli in a basket-
like fashion. Contraction of the myoepithelial cells expels the milk into the
interlobular excretory ducts (2, 6).

FIGURE 21.42 ■ Mammary gland during lactation. Stain: hematoxylin and

eosin. Left, medium magnification; right, high magnification.

FIGURE 21.43 | Lactating Mammary Gland

This photomicrograph illustrates a lobule of a lactating mammary gland that is
separated from the adjacent lobule by a layer of connective tissue (5). The
alveoli (2, 3) contain secretory product (6) (milk) and are separated by
connective tissue septa (5). Some alveoli (3) are single, whereas others are
branching alveoli (2). All the alveoli drain into larger excretory ducts that deliver

the milk to the lactiferous ducts in the nipple. The mammary glands contain large
amounts of adipose tissue (1, 4) during lactation.

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