Pancreas exocrine secretion Flashcards
What is the Difference between exocrine and endocrine secretion?
Exocrine- secretes substances into a ductus system
Endocrine- secretes substance directly into the blood
What ion does the pancreas secrete to neutralise stomach acid in the small intestine?
What rate does it produce at?
Bicarbonate ion
1 litre/24 hours
What are 2 Functions of Bicarbonate in the duodenum?
Protects duodenal mucosa
Buffers duodenal contents to optimise pH for enzyme digestion
What are the two proteases secreted by the pancreas? How are they stored?
Trypsin and Chymotrypsin
Stored as proenzymes which are Trypsinogen and Chymotrypsinogen
What activates Trypsinogen to produce trypsin?
What activates Chymotrypsinogen to produce chymotrypsin?
Enterokinase converts trypsinogen into trypsin
Trypsin converts chymotrypsinogen into chymotrypsin
What does the exocrine pancreas secrete that converts triglycerides into monoglycerides?
Lipases
What innervates enzyme secretion in the cephalic stage? What does this cause to be released and from where?
Vagus nerve
Gastrin, G cells
What 3 hormones are released in the intestinal stage of enzyme secretion in the exocrine pancreas?
Secretin
Cholecystokinin
Gastrin
What stimulates the hormone Cholecystokinin?
HCL, proteins and fats entering duodenum
Where is Cholecystokinin produced?
I cells (Duodenum and Jejunum)
5 Actions of Cholecystokinin?
Pancreatic enzyme and bicarbonate secretion
Gallbladder contraction
Inhibition of Gastric acid secretion
Delays gastric emptying
What stimulates the hormone secretin?
Low duodenal pH
Where is secretin produced?
S cells in small intestine
Action of secretin?
Pancreatic juices and bicarbonate secretion
Pancreatic exocrine insufficiency 4 symptoms?
Maldigestion, Diarrhoea, Steatorrhoea (Excess of fat in faces) and weight loss
