pancreas
(pang'krē-ăs 
)
(pan'krē-ăs)
(pan-krē'ăt-ă)
Plural: pancreases
pancreata
[ pan- + Gr. kreas, stem kreat-, flesh, meat]
A compound acinotubular gland located behind the stomach and in front of the first and second lumbar vertebrae. The head lies within the curve of the duodenum, the tail lies near the spleen, and the middle portion constitutes the body. The pancreas is both an exocrine and an endocrine organ. The exocrine gland s are acini, each with its own duct; these ducts anastomose to form the main pancreatic duct or duct of Wirsung, which joins the common bile duct and empties into the duodenum at the hepatopancreatic ampulla. An accessory pancreatic duct or duct of Santorini is often present and opens into the duodenum directly. Scattered throughout the exocrine gland ular tissue are masses of cells called islets of Langerhans, endocrine gland s that secrete hormones.
SEE: illus..
Function: The exocrine secretion of the pancreas consists of enzymes that digest food in the small intestine, and sodium bicarbonate to neutralize hydrochloric acid from the stomach in the duodenum.
SEE: pancreatic juice.
The islets of Langerhans contain alpha, beta, and delta cells. Alpha cells secrete glucagon, which raises blood glucose; beta cells secrete insulin, which lowers blood glucose; delta cells secrete somatostatin, which inhibits the secretion of insulin, glucagon, growth hormone from the anterior pituitary, and gastrin from the stomach.
Diseases of the Pancreas: Autoimmune damage to the islets of Langerhans results in type 1 diabetes mellitus, a disease in which insulin secretion is insufficient or completely absent. Insulin-secreting tumors of the pancreas, called insulinomas, produce hypoglycemia; they are exceptionally rare. Inflammation of the pancreas, known as pancreatitis, is a common condition that often results from excessive use of alcohol or from obstruction of the exocrine secretions of the pancreas by gallstones. Pancreas divisum is a common congenital anomaly in which the main duct of the exocrine pancreas drains into an accessory pancreatic papilla instead of the duodenal papilla; it has been associated with recurring episodes of pancreatitis.
SEE: diabetes mellitus; insulin; pancreatic function tests.
accessory p.A small mass of pancreatic tissue close to the pancreas but detached from it.
annular p.An anomalous condition in which a portion of the pancreas encircles the duodenum.
p. divisum A congenital anomaly in which the dorsal and ventral pancreatic ducts fail to unite during embryonic development. It has been associated with pancreatitis.
dorsal p.A dorsal outpocketing of the embryonic gut that gives rise to the body and tail of the adult pancreas.
lesser p.The semidetached lobular part of the head of the pancreas, sometimes having a separate duct opening into the main one. SYN: uncinate process of the pancreas.
ventral p.An outgrowth at the angle of the hepatic diverticulum and the embryonic gut that migrates and fuses with the dorsal pancreas. It forms the head of the definitive organ.
SEE: under Willis, Thomas.