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Flashcards in THE PANCREAS Deck (36)
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1

what does the exocrine pancreas produce?

aqueous HCO3- and enzyme secretion

2

what does the endocrine pancreas produce?

insulin and glucagon

3

what do alpha cells of the pancreas secrete?

glucagon

4

what do beta cells of the pancreas secrete?

insulin

5

what are pancreatic islets?

made of alpha and beta cells
secrete insulin and glucagon into the bloodstream

6

what is the role of acini cells in the pancreas?

secrete enzymes to the pancreatic duct

7

what is the role of centroacinar cells?

produce HCO3-

8

what is the role of ductable cells?

HCO3- and Cl- exchange via CFTR channels

9

what proteases are produced by the pancreas?

typsin and chymotrypsin
these are released as zymogens trypsinogen and chymotrypsinogen

10

where are proteases secreted by the pancreas activated?

in the small intestine

11

what activates proteases that are secreted by the pancreas

enterokinase
trypsin can also activate trypsinogen via positive feedback loop

12

what are the products of hydrolysis of triglycerides by pancreatic lipases?

monoglyceride and free fatty acid chains

13

what is dietary fat absorption highly dependent on?

pancreatic and hepatic secretion

14

what can pancreatic insufficiency cause?

steatorrhea (fatty stools)

15

what is the role of amylase?

hydrolyses starch to maltose and dextrins

16

what is primary secretion of the pancreas?

NaHCO3

17

what is secondary secretion of the pancreas?

HCO3- is exchanged for Cl-

18

what is the fluid composition of pancreatic secretions dependent on?

it is dependent on the flow rate - the faster the flow, the less exchange takes place
this means it is richer in HCO3- and lower in Cl-
Na+ and K+ levels do not change

19

which ions change in pancreatic secretions?

HCO3- and Cl-
Na+ and K+ levels do not change

20

what is the composition of pancreatic fluid during the resting phase (low flow)?

predominantly Na+ and Cl-

21

what is the composition of pancreatic fluid during high flow?

mainly Na+ and HCO3-

22

what volume of pancreatic secretion is produced each day?

1 litre

23

what is the functions of bicarbonate secretion in the pancreas?

- it protects the duodenal mucosa by neutralising acid
- buffers duodenal contents
- optimises pH for enzyme digestion

24

how is the HCO3- component of pancreatic secretion regulated?

- mainly stimulated by production of acid in the stomach
- neutralising effect
- stimulated by secretin and CCK

25

how is the enzymatic component of pancreatic secretion regulated?

- secreted by acinar cell in response to increased intracellular Ca2+ concentration
- produced by ACh from vagal stimulation
- CCK secreted from small intestine can stimulate enzyme release

26

which regulatory phase has the most impact on pancreatic secretion?

intestinal
- cephalic and gastric phases also have an effect

27

what is the stimulus for CCK secretion?

HCl, proteins and fats in the duodenum

28

where is CCK produced?

in I cells of the duodenum and jejunum

29

what is the action of CCK?

- pancreatic enzyme and HCO3- secretion
- gallbladder contraction (causing bile secretion)
- inhibition of gastric acid secretion
- delays gastric emptying (aid digestion)

30

what is the stimulus for secretin secretion?

low duodenal pH