Pancreatic secretions

Question 1

Regulation of pancreatic secretions

• parasympathetic
• secretin
• CCK

Answer 1

Parasympathetic
-via X => secretion of enzymes

Secretin
-acidic chyme in duodenum via S cells => increased HCO3

CCK
-acidic chyme in duodenum via I cells => increased enzyme prod/bile release via GB contractions

Question 2

Describe the route of pancreatic secretions from the acinar cells, duct cells

Answer 2

Active secretion, unaffected by hydrostatic pressure in blood

Acinar cells produce NaCl and zymogen rich secretion

Duct cells produce HCO3 secretion

Pancreatic duct joined by common bile duct => major duodenal papilla

Question 3

Contents of zymogens

Whats special about the peptidases

Answer 3

Amylase
Lipase
Trypsinogen
Chymotrypsinogen

Peptidases activated by Enteropeptidase

Question 4

Describe the adaptations and constituents of the acinar cells

Answer 4

Many RER
Golgi
Zymogen granules

Question 5

Describe the adaptations of the duct cells

Describe its function

Answer 5

MANY MITOCHONDRIA FOR ACTIVE SECRETION
Carbonic anhydrase => H, HCO3

NaH antiporter

• H secreted into blood
• Na removed by NaKATPase from duct cell

NaKCl triporter
-All move into duct cell

HCO3 Cl antiporter

• HCO3 into lumen
• Cl transported into lumen