On this section of pancreas, make sure you can identify lobules, connective tissue septa, ducts and islets of Langherans.
In this magnified section of pancreas shows the secretory acini of the exocrine pancreas.
Identify the secretory acini, duct, septa and blood vessels.
The pancreas is the main enzyme producing accessory gland of the digestive system. It has both exocrine and endocrine functions.
The exocrine part of the pancreas has closely packed serous acini, similar to those of the digestive glands. It secretes an enzyme rich alkaline fluid into the duodenum via the pancreatic duct. The alkaline pH is due to the presence of bicarbonate ions, and helps to neutralise the acid chyme from the stomach, as it enters the duodenum. The enzymes digest proteins, carbohydrates, lipids and nucleic acids. These enzymes include: trypsin and chymotrypsin (secreted as inactive precursors, and activated by the action of enterokinase, an enzyme secreted by the duodenal mucosa). An enzyme called CCK stimulates the release of these enzymes, from stored granules in the secretory cells of the acini. Secretin (from neuroendocrine cells in the small intestine) stimulate the release of watery alkaline secretions.
The endocrine part of the pancreas, consists of isolated islands of lighter staining cells called islets of Langerhans. The secretions of the acini empty into ducts lined with a simple low cuboidal epithelium, which becomes stratified cuboidal in the larger ducts.