PANCREATIC JUICE: CHARACTERISTICS, FUNCTION AND COMPOSITION - ANATOMY AND PHYSIOLOGY - 2025

The pancreatic juice is a clear liquid secreted by the pancreas mainly composed of water, electrolytes and enzymes. The pancreas plays an important role in the digestion of food and it is the enzymes found in pancreatic juice that allow the body to break down carbohydrates, proteins, and fats.

Pancreatic juice is composed of water, mineral salts, enzymes, amylase, lipase, inactive enzyme precursors, trypsinogen and chymotrypsinogen, and procarboxypeptidase. The alkaline nature of pancreatic juice is attributed to the presence of bicarbonate ions, which are alkaline in solution.

Composition

Pancreatic enzymes

The pancreas creates natural juices called pancreatic enzymes to break down food. These juices travel through the pancreas through ducts, and empty into the duodenum. Each day, the pancreas produces about 200 ml of digestive juice packed with enzymes. These are:

Lipase

This enzyme works with bile, which is produced by the liver, to break down fat. If you don't have enough lipase, your body will experience problems absorbing fat and important fat-soluble vitamins (A, D, E, K). Symptoms of fat malabsorption include diarrhea and fatty bowel movements.

Protease

This enzyme breaks down the proteins we eat. It also helps protect us from germs that can live in the intestines, such as certain bacteria and yeasts. Undigested proteins can cause allergic reactions in some people.

Amylase

This enzyme helps break down starches into sugar, which the body can use for energy. An amylase deficiency can cause diarrhea from undigested carbohydrates.

Pancreatic hormones

Many groups of cells produce hormones within the pancreas. Unlike enzymes that are released in the digestive system, hormones are released into the blood and carry messages to other parts of the digestive system. Pancreatic hormones include:

Insulin

This hormone is produced in cells of the pancreas known as beta cells. Beta cells make up about 75% of pancreatic hormone cells.

Insulin is the hormone that helps the body use sugar for energy. Without enough insulin, your blood sugar levels rise and you develop diabetes.

Glucagon

Alpha cells represent about 20% of the cells of the pancreas that produce hormones, they produce glucagon. If your blood sugar level is too low, glucagon helps raise it by sending a message to the liver to release stored sugar.

Gastrin and Amylin

Gastrin is produced mainly in G cells in the stomach, but it is also produced in the pancreas and its function is to stimulate the stomach to produce gastric acid. Amylin is produced in beta cells and helps control appetite and stomach emptying.

Functions of pancreatic juice

Protein digestion

Enteropeptidase converts trypsinogen and chymotrypsinogen to the active proteolytic enzymes trypsin and chymotrypsin, which convert polypeptides to tripeptides, dipeptides, and amino acids.

Carbohydrate digestion

Pancreatic amylase aids in the conversion of digestible polysaccharides -starch- by salivary amylase to disaccharides.

Digestion of fats

Bile salts help lipase in converting fats into fatty acids and glycerol.

What is the pancreas?

The pancreas is a spongy, tube-shaped organ about 15 centimeters long. It is located in the back of the abdomen, behind the stomach and connected to the duodenum.

The pancreas is a vital digestive organ because it produces a variety of enzymes that break down all the major food groups.

These enzymes are secreted into the duodenum along with a high concentration of bicarbonate. Bicarbonate makes pancreatic secretions alkaline in nature.

The pancreas produces pancreatic juices and hormones. Pancreatic juices contain enzymes that help digest food in the small intestine.

Among the hormones made by the pancreas, insulin stands out, which controls the amount of sugar in the blood. Both enzymes and hormones are necessary for the proper functioning of the body.

This flow of alkaline fluid in the small intestine helps neutralize the acid chyme that comes from the stomach.

Chyme consists of the partially digested food mass that has just come out of the stomach. Neutralizing the acid chyme provides a better environment for the activation of pancreatic enzymes.

Once produced, the pancreatic juices flow into the main pancreatic duct. This duct joins the bile duct, which connects the pancreas with the liver and gallbladder.

The common bile duct, which carries bile (a fluid that helps digest fat), connects to the small intestine through an opening called a bleb in the duodenum near the stomach.

Functions of the pancreas

A healthy pancreas produces the right chemicals in the right amounts, at the right times, to digest the food we eat.

Exocrine function

The pancreas contains exocrine glands that produce enzymes important for digestion. These enzymes include: trypsin and chymotrypsin to digest proteins; Amylase for the digestion of carbohydrates; and lipase to break down fats.

When food enters the stomach, these pancreatic juices are released into a system of ducts that culminate in the main pancreatic duct.

The pancreatic duct joins the common bile duct to form the ampulla of Vater (or greater duodenal papilla) which is located in the first portion of the small intestine, called the duodenum.

The common bile duct originates from the liver and gallbladder and produces another important digestive juice called bile. The pancreatic juices and bile that are released into the duodenum help the body digest fats, carbohydrates and proteins.

Endocrine function

The endocrine component of the pancreas consists of islet cells (called islets of Langerhans or pancreatic islets) that create and release important hormones directly into the bloodstream.

Two of the main pancreatic hormones are insulin, which works to lower blood sugar, and glucagon, which works to increase blood sugar.

Maintaining proper blood sugar levels is crucial for the function of key organs such as the brain, liver, and kidneys.

References

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