Function of the pancreas | Function of the pancreas

Function of the pancreas

The pancreas has two important functions, which must be distinguished from each other. Firstly, it is the largest and most important digestive gland and secondly, it regulates the blood sugar level via the hormone insulin. As a digestive gland, the pancreas produces about 1.5 l of digestive juice (also known as pancreatic juice) daily.

This juice contains substances that the human body needs to break down the substances found in food into smaller and smaller pieces, i.e. to digest them. These substances are also called digestive enzymes (amylases, lipases, proteases). Since the pancreas releases its digestive juice directly into the duodenum through an excretory duct, this function of the pancreas is called “exocrine” (secreting from glands to the outside).

In addition to this exocrine gland function, the pancreas also has an endocrine glandular part. Endocrine means that something is secreted directly into the blood without an excretory duct. In the pancreas, approximately 2% of the organ performs an endocrine function.

These parts of the pancreas are also called the “islets of Langerhans” because the endocrine cells form islands and produce pancreatic hormones such as insulin. This part of the pancreas regulates the blood sugar level by releasing hormones, especially after eating food rich in carbohydrates. With the production of the hormones insulin and glucagon, the pancreas assumes a central function in the regulation of the blood sugar balance.

The key word here is glucose, which is an important – if not the most important – substrate for the body’s energy supply. The hormone glucagon ensures an increased supply of glucose in the blood. For example, it ensures that new glucose is produced in the liver and muscles (gluconeogenesis) and that glucose stores are broken down by releasing individual glucose molecules (glycogenolysis).

This is especially necessary when the body needs energy. The counterpart to glucagon is insulin, which is also produced by the pancreas. It has the function that glucose is absorbed from the blood into the cells and is metabolised or stored in storages.

Insulin is increasingly produced after eating, because a particularly large amount of glucose is then washed away with food. The production of digestive juices and hormones occurs largely independently of each other. This means that both functions of the pancreas can also be disrupted independently of each other if for any reason the pancreas is damaged.

  • Carbohydrates
  • Fats and
  • Proteins

The release of digestive juice through the pancreas is stimulated by food intake. The autonomic nervous system identifies food intake when the stomach wall expands due to the filling and reacts by activating the pancreas. In addition, various hormones such as secretin (from the duodenum), lead to the release of digestive juice.

In the pancreas itself, the substances (enzymes) that make up the pancreatic juice are stored as so-called precursors. This means that they cannot yet break down starch, proteins and fats. Only after being released from the pancreas through the excretory duct do these substances become effective at their destination, the small intestine.

The composition of the digestive juice depends on the type of food ingested. For example, if very fatty food is ingested, more fat-cleaving enzymes (so-called lipases) are released. If these enzymes are missing, the food components are not broken down properly and cannot be absorbed into the bloodstream from the intestine.

As a result, undigested food continues to migrate through the intestines, leading to flatulence and diarrhoea. In addition, the lack of nutrient absorption can lead to other symptoms such as weight loss, lack of vitamins and organ dysfunction. The second function of the pancreas is blood sugar regulation, which intervenes when carbohydrate-rich food is consumed.

In response to elevated blood sugar levels, the B cells of the pancreas secrete insulin, because it is the only hormone in our body that can lower blood sugar levels. Insulin enables sugar, especially glucose, to be absorbed from the blood into the various cells of the body. Dextrose is the most important energy supplier for all cells of the body.

Especially the liver and muscle cells can absorb a lot of sugar in a short time. There the sugar is either stored or directly converted into energy. In contrast, when the blood sugar level in the blood drops sharply, the A-cells of the pancreas release the hormone glucagon.

Glucagon causes the sugar reserves to be released from the liver and thus leads to an increase in the blood sugar level. This means that the body cells continue to be supplied with glucose and receive sufficient energy to maintain their function. This topic might also be of interest to you: Hypoglycemia – what happens in hypoglycemia?