The neck arises from the left upper part of the front of the head. The endocrine part is composed of hormonal tissue distributed along the pancreas in discrete units called islets which pancreatic enzymes functions in the digestion of proteins Langerhans. Islets of Langerhans have a well-established structure and form density routes through the exocrine tissue. These supply the head of the pancreas. With increasing diameter, several layers of columnar cells may be seen.
The size of the pancreas varies considerably. The pancreas develops from these buds on either side of the duodenum. This condition has no physiologic consequence. An additional ventral lobe that usually regresses during development is omitted. Each structure communicates with the foregut through a duct. Differential rotation and fusion of the ventral and dorsal pancreatic buds results in the formation of the definitive pancreas.
Upon reaching its final destination, the ventral pancreatic bud fuses with the much larger dorsal pancreatic bud. At this point of fusion, the main ducts of the ventral and dorsal pancreatic buds fuse, forming the main pancreatic duct. Differentiation of cells of the pancreas proceeds through two different pathways, corresponding to the dual endocrine and exocrine functions of the pancreas. Development of the exocrine acini progresses through three successive stages. These are the predifferentiated, protodifferentiated, and differentiated stages, which correspond to undetectable, low, and high levels of digestive enzyme activity, respectively. Blood glucose levels are maintained at a constant level in the body by a negative feedback mechanism. When the blood glucose level is too high, the pancreas secretes insulin and when the level is too low, the pancreas then secretes glucagon.
The flat line shown represents the homeostatic set point. The sinusoidal line represents the blood glucose level. Within these islets are four main types of cells which are involved in the regulation of blood glucose levels. These act to control blood glucose through secreting glucagon to increase the levels of glucose, and insulin to aplication of enzymes in food industry it. The islets are crisscrossed by a dense network of capillaries.
The islets function independently from the digestive role played by the majority of pancreatic cells. This role is called the “exocrine” role of the pancreas. The cells are filled with granules containing the digestive enzymes. The pancreas secretes substances which help in the digestion of starch and other carbohydrates, proteins and fats.
Less than 100 of these genes are more specifically expressed in the pancreas. A perforation of the pancreas, which may lead to the secretion of digestive enzymes such as lipase and amylase into the abdominal cavity as well as subsequent pancreatic self-digestion and digestion and damage to organs within the abdomen, generally requires prompt and experienced medical intervention. It is possible for one to live without a pancreas, provided that the person takes insulin for proper regulation of blood glucose concentration and pancreatic enzyme supplements to aid digestion. Inflammation of the pancreas is known as pancreatitis. In pancreatitis, enzymes of the exocrine pancreas damage the structure and tissue of the pancreas. There are several types of pancreatic cancer, involving both the endocrine and exocrine tissue.