The endocrine portions of the pancreas are the pancreatic islets, small clusters of cells within the pancreatic tissue. The term islet, meaning "small island," is used because these cells look like little islands in the midst of the many pancreatic cells that secrete digestive juices (Fig. 1). The islet cells produce two hormones, insulin and glucagon, that regulate sugar metabolism. Insulin increases cellular use of glucose, thus decreasing sugar levels in the blood. Glucagon has the opposite effect of increasing blood sugar levels.

FIGURE 1. Microscopic view of pancreatic cells. Light staining islet cells are seen among the cell clusters that produce digestive juices. (Reprinted with permission from Cohen BJ, Wood DL. Memmler's The Human Body in Health and Disease. 9th Ed. Philadelphia: Lippincott Williams & Wilkins, 2000.)

责任编辑：admin