Pancreas
Anatomy
Enzymes
Functions
Metabolism
endocrine function that regulates blood sugar
aides in the digestive process
exocrine function that helps in digestion
The pancreas is composed of two different tissues; exocrine and endocrine tissues.The endocrine tissues are hormone producing and consists of the islets of Langerhans, which secrete at least 4 hormones into the blood; insulin, glucagon, gastrin, somatostatin.
beta cells of the islet of Langerhans produce insulin- lowers blood glucose
proteolytic enzymes: trypsin, chymotrypsin, elastase, collagenase, leucine aminopeptidase, and carboxypeptidases
lipid digesting enzymes: primarily lipase and licithinase
carbohydrate-splitting pancreatic amylase
several nucleases (ribonucleases), which separate the nitrogen-containing bases from their sugar-phosphate strands.
Exocrine pancreatic (enzyme-secreting) component secretes fluid rich in digestive enzymes
the digestive enzymes secreted by the pancreas are capable of digesting the 3 major classes of food substances; proteins, carbohydrates, and fats.
Digestive fluid is produced by pancreatic acinar cells, which line the pancreas and are connected by small ducts, forming one major duct and a smaller accessory duct.
The pancreas is a long, tapered organ located behind the stomach. The "head", the right side of the organ, is the widest part and lies in the curve of the duodenum, the first division of the small intestine. The left side is the tapered end that extends slightly upward, is the body of the pancreas. The "tail" or the end, ends near the spleen.
alpha cells produce glucagon- raises blood glucose
somatostatin prevents the release of insulin and glucagon
Trypsin is produced by the pancreas in an inactive form called trypsinogen.Trypsin helps digest protein.
Chymotrypsin is a digestive enzyme that breaks down proteins. It is secreted in a non-active form so it will not break down the pancreas.
Elastase is transported to the small intestine to break down fats, proteins, and carbohydrates as part of food digestion
Collagenases are enzymes that break the peptide bonds in collagen. They assist in destroying extracellular structures in the pathogenesis of bacteria such as Clostridium.
Carboxypeptidase is an enzyme synthesized in the pancreas and secreted into the small intestine. This enzyme hydrolyzes the first peptide or amide bond at the carboxyl or C-terminal end of proteins and peptides.
Most of the pancreatic action is under the hormonal control of secretin and cholecystokinin (CCK)
Secretin is responsible for the production of bicarbonate-rich, alkaline pancreatic fluid, which protects the lining of the intestine from damage
CCK is produced by the cells of the intestinal mucosa ans s responsible for release of enzymes from the acinar cells by the pancreas into the pancreatic fluid.
Leucyl aminopeptidases are enzymes that preferentially catalyze the hydrolysis of leucine residues at the N-terminus of peptides and proteins