Page 640 - Atlas of Histology with Functional Correlations

FIGURE 16.13 ■ Pancreatic islet. Stain: hematoxylin and eosin. High
magnification.

FIGURE 16.14 | Pancreatic Islet (Special

Preparation)

This pancreas has been prepared with a stain to distinguish the glucagon-
secreting alpha (A) cells (1) from the insulin-secreting beta (B) cells (3). The
cytoplasm of alpha cells (1) stains pink, whereas the cytoplasm of beta cells (3)
stains blue. The alpha cells (1) are situated more peripherally in the islet, and the

beta cells (3) more centrally. Also, the predominant beta cells (3) constitute
about 70% of the islet. Delta (D) cells (not illustrated) are also present in the
islets. These cells are least abundant in the islets, have a variable cell shape, and
may occur anywhere in the pancreatic islet.

Capillaries (2) around the endocrine cells demonstrate the rich vascularity

of the pancreatic islets. The thin connective tissue capsule (4) separates the islet
cells from the serous acini (6). Centroacinar cells (5) are visible in some of the
acini.

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