The Pancreas

The pancreas is a bilobed, lobulated, elongated gland located in the right, dorsal abdo­men. The right lobe lies in contact with the descending duodenum and the left lobe lies in the dorsal leaf of the greater omentum (see Section 3.2).

The pancreas has both an endocrine and an exocrine function. The pancreatic islets (islets of Langerhans) produce the endocrine secretions, insulin (beta cells), glucagon (alpha cells), somatostatin (delta cells) and pancreatic polypeptide (gamma cells), and their function is mainly the regulation of blood sugar levels. The exocrine function is the secretion of pancreatic juice containing digestive enzymes for action on carbohydrates, proteins and fats within the duodenum. The alkalinity of the pan­creatic juice is maintained by the production of bicarbonate, which neutralises the acidic gastric juice.

The pancreas has two excretory ducts in the horse and dog. The pancreatic duct is the larger in the dog and is located on the ventral side of the duodenum in close associa­tion to the opening of the common bile duct. The accessory pancreatic duct enters the duodenum on its dorsal side. The ruminants and the pig have only one pancreatic duct (it is the accessory duct that is present).

7.7