Measuring about 12 to 15 centimeter in length, pancreas is a glandular organ lying behind stomach in the abdomen and performing both endocrine as well as exocrine functions. The exocrine secretions (pancreatic juice) are released into the duodenum of small intestine through pancreatic duct. The pancreatic fluid is of great importance for the digestive system as it contains a number of biological catalysts (enzymes) that carry out breakdown of carbohydrates, fats, proteins and other components of chyme into simpler absorbable molecules. The internal or endocrine functions include the secretion of vital hormones, viz. somatostatin, glucagon, insulin and pancreatic polypeptide that carry out a number of important functions in the body.
Islets of Langerhans are the clusters of cells that are about one million in number and are collectively involved in the secretion of hormonal substances that are poured directly into the blood stream and delivered to various target organs in the body. If any of such secretions are disturbed or blocked, functions of pancreas are badly affected and your body will be unable to perform a number of vital functions that consequently lead to severe medical conditions. Let us have an overview of the pancreatic hormones with the sites of their secretion and associated functions:
Insulin, One of the most important hormones, it is produced by beta cells in pancreas and regulates the metabolic processes of fats and carbohydrates in the body especially by lowering the increased levels of blood sugar. Extra sugar molecules in the bloodstream are absorbed by fat cells, skeletal muscles and liver where these are converted into storage compounds, like glycogen.
Somatostatin, Secreted by delta cells of pancreas, the peptide hormone is transported to various part of the body for performing its prohibiting and regulatory role in the endocrine system of the body. Some of the important functions of the Somatotropin Release Inhibiting Hormone include the inhibition of GH (growth hormone), TSH (thyroid stimulating hormone), gastrointestinal hormones and the suppression of pancreatic hormones.
Glucagon, This peptide hormone performs functions that contrast with that of insulin as the former increases the level of blood sugar while the latter lowers the elevated level of blood sugar. Responding to the abnormally low contents of sugar, glucagon is released that stimulates the cells in liver for the conversion of glycogen into glucose which is then poured into the bloodstream.
Pancreatic Polypeptide, Abbreviated as PP, it is a self-regulating substance secreted by gamma cells in the pancreas that controls both endocrine and exocrine activities of the organ. Its secretion is triggered by exercise, fasting or eating proteinaceous meal while somatostatin and injection of intravenous glucose suppress its production.
In this type of pancreas function, the secretions are not utilized internally, but are transported to the duodenum of small bowel via a tube called pancreatic duct. The pancreatic juice contains a number of valuable substances (e.g. digestive enzymes) that facilitate the functions of your gastrointestinal system, especially the breakdown of dietary contents, viz. fats, saccharides, and proteins. Some of the most important exocrine functions of pancreas can be summarized as under:
The partly digested food mass (chyme) that enters the duodenum through pyloric sphincter is highly acidic in nature. It needs to be neutralized with the help of alkaline pancreatic fluid for providing an optimum pH medium for the enzymes in small intestine to act upon them.
A variety of pancreatic enzymes (amylase, pancreatic lipase, nucleases, trypsinogen, and elastase, etc.) are effectively involved in the further breakdown of partly digested food. After the complex dietary components are finally broken down into simpler molecules, they are absorbed directly into the bloodstream across the intestinal wall and are transported to every cell in the body for the extraction of energy in the form of ATP (Adenosine Tri-Phosphate).