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How do the exocrine and endocrine parts of the pancreas differ?

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An anatomical illustration of the human pancreas shows its location near the stomach and intestines, a detailed cross-section highlighting ducts and the islet of Langerhans, and an inset of pancreatic tissue histology with labeled alpha, beta, and delta cells. — pancreatic cancer The human pancreas is composed of two main types of tissue: acinar cells and islets of Langerhans. The acinar cells produce digestive enzymes, which are secreted into tiny ducts that feed into the pancreatic duct. Islets of Langerhans are clusters of cells that secrete hormones such as insulin and glucagon directly into a capillary network, which also joins the pancreatic duct.

The pancreas is a dual-function gland composed of two distinct types of tissue: the exocrine pancreas and the endocrine pancreas.12

Exocrine Pancreas

The exocrine pancreas, which constitutes the majority of the organ's mass, is primarily composed of acinar cells. Its function is to secrete digestive enzymes—such as proteases, lipases, and amylases—into the digestive tract to aid in the breakdown of proteins, fats, and carbohydrates. These secretions are transported through a system of ducts into the small intestine.312

Endocrine Pancreas

The endocrine pancreas consists of islets of Langerhans, which are clusters of cells scattered throughout the gland. Unlike the exocrine tissue, this is a ductless system that secretes hormones directly into the bloodstream. Key hormones include insulin and glucagon, which are essential for regulating blood sugar levels, as well as somatostatin and vasoactive intestinal polypeptide, which help control intestinal motility and secretion.4125