When considering the structure of the pancreas, it should be noted that this is a fairly large gland located on the back of the abdomen behind the stomach. The first mention of it was found in the Talmud, but then no one knew about the anatomical and histological structure. It was referred to as a small organ located next to the duodenum. Much later, with a more detailed study of the structure of this organ, it was found that it consists of three main parts: the
- of the head, which occupies the main part and has the shape of a hook process,
- of a body shaped like a prism separated from the head by a small furrow, the
- tailcan be bent up or slightly down.
Topography and anatomical structure of the pancreas
Topography and analysis of the structure of the human body show that the pancreas occupies a very convenient place. Its head is located next to the 1st lumbar vertebra in an adult, and in a baby it is raised a little higher( located about 10-11 thoracic vertebra).The body and tail go to the left and rise slightly upward. So the end of the tail is in the area of the 11-12 rib on the left. This organ is considered quite large, its length reaches from 15 to 20 cm, but it occurs, although rarely up to 24 cm. The width of the organ is within 2-3 cm, and in the head area the thickening reaches 7-8 cm. It weighs in the adultslightly less than 100 g. At birth, it weighs only 2-3 g of babies. The entire surface of the organ is grayish pink in color.
Its head is facing the duodenum, hiding in the formed loop. The body in front is covered and protected by the stomach, so it got its name, and the tail firmly rests against the spleen.
Pancreatic acinus, consisting of secretory and duct cells, is the structural unit of this organ. This small rounded shape giving rise to the entire numerous
duct system Histology of the pancreas
The internal histological structure of the human pancreas and its functions are quite interesting and unusual, differ significantly from other organs. The small lobules that make up the organ are its main mass. Their main function is an exocrine function. There is a secret in the ducts that are inside the lobules. Between them are interlayers containing nerves and small blood vessels. Inside, they are expelled by a cylindrical epithelium, exactly the same as the main duct.
Noting the features of the histological structure of the pancreas, it is worth considering the characteristics of the small pancreatic islets of Langerhans, which are endocrine formations. It is they who produce insulin and glucagon in the blood, which determine the sugar rate in our body. Insulin lowers it, in glucagon - it increases. Most of all these islets are in the tail.
Through the entire organ from the head to the tail stretched the pancreatic duct, along which the secret moves from the exocrine part. Throughout the way, small channels of numerous lobes flow into it. The pancreatic duct, encountering the bile duct, flows into the mouth of the papilla of the duodenum.
Some people have peculiarities in the structure of the pancreas. In the thin wall of the stomach or duodenum there are small nodules. This is an additional gland. However, it does not have a direct link to the main body.
The functions are connected with the structure. It performs the endocrine and exocrine role, or, in simple terms, conducts external and internal secretion.
Pancreas location in the human body
The pancreas is relatively large in size relative to the rest of the digestive system, but it is not possible to determine its location in a healthy person by palpation. To determine the exact position and structure of the body, MRI, ultrasound, or computerized research is used.
The pancreas, which consists of a number of lobules, is conventionally divided into a head, body and tail. The "head" part of the body lies on the right side of the pair of upper vertebrae of the lumbar spine.
To ensure a static state, the head of the organ is braided by the twist of the duodenum. The posterior edge of the "head" part is attached to the renal blood vessels. The serous membrane of the inner peritoneal sheet protects the head from above.
Further up and to the left follows the narrow and short part of the body, called the isthmus. It is the link between the head and the body of the pancreas. Under the isthmus are some parts of the small intestine.
The main part of the organ( body) resembles a polyhedron and is located on the same level as the first lumbar vertebrae. The back part of the body is covered by the left kidney and adrenal gland, large blood vessels, mesenteric lymph nodes and solar plexus. In front of the body is a slit-shaped space of the abdominal cavity and stomach.
The tail of the pancreas is curved arcuate, in contact with the gates of the spleen. Here part of the colon passes.
The location of the body varies slightly depending on the natural position of the body. In the "lying" position, the iron is located under the stomach, in the "standing" position - behind the stomach, in contact with the duodenum.
Functions and hormones of the pancreas
The body is extremely important in providing vital activity of the body, as it is responsible for performing the external and intrasecretory functions.
As an organ of external secretion, the pancreas stimulates the release of pancreatic juice into the ducts of the duodenum. This liquid includes a number of enzymes( amylase, trypsin, lipase, etc.), which neutralize gastric acid, taking an active part in the process of digestion of food.
Intrasecretory function is responsible for the production of hormones( insulin glucagon and lipocaine).Glucagon and insulin, being hormone-antagonists, participate in carbohydrate metabolism and maintain the level of glucose in the blood within normal limits. Lipokain promotes the synthesis of phospholipids, which stimulates the oxidation of fatty acids and blocks the formation of fat deposits in the liver.
Microscopic structure of the pancreas
Acinar cells are a structural and functional unit of the pancreas. These formations consist of a dozen epithelial, a small number of centrally centered cells, connected by secretory capillaries and an intra-lobular duct. Plasma membranes pass between the acinar cells. The main function of cells is the production of protein secretion.