Pancreas

List the three key cell types that are important to the exocrine function of the pancreas and their secretions.

1. Acinar Cells: Highly effective at protein synthesis; secrete digestive enzymes and fluid 2. Duct Cells: Primarily secrete fluid and bicarbonate; ion transfer 3.Goblet Cells: Specialize in mucin synthesis and secretion

Know and understand the following pathophysiological conditions and symptoms: pancreatitis.

1. Calcium and Pancreatitis: Often pancreatitis is associated with an obstruction of the common biliary or pancreatic duct as well as alcoholism -Misregulated cellular calcium plays a significant role -Tissue damage to the pancreas release of pancreatic enzymes digest itself inflammatory cells mediators damage to distal sites -Malabsorption: Due to decreased secretion of digestive enzymes into the duodenum 2. Pancreatic Cancer: Usually an adenocarcinoma -Causes: Chronic pancreitis, smoking, high fat diets, diabetes, -Mutation to p53

Identify the two primary stimuli for fluid and enzyme secretion by pancreatic acinar cells.

1. Primary enzyme stimulation: CCK and Ach 2. Fluid: Ach and CCK also increase activity of chloride ion channel increase in fluid into the lumen *Can be further enhanced by VIP or secretin

4. Identify the primary stimulus for the secretion of bicarbonate from pancreatic duct cells.

A. Duct cells are stimulated by secretin from duodenal cells in response to low pH: Secrete bicarb: acid buffer

3. Describe how zymogens are stored in the pancreas and activated in the duodenum.

A. Protection/ Storage: Vesicles low pH? B. Activation: Trypsinogen is converted to trypsin: in the duodenum by enterokinase; trypsin can then initiate the activation of other zymogens

Identify the stimulus for returning the levels of pancreatic secretion from the fed state to the interdigestive state. ***

Fats reach the ileum release of peptide YY and somatostatin decrease in pancreatic secretions interdigestive state