gastroenterology - pancreas and small bowel

Question 1

What are first 2 steps of pancreatic embryology?

Answer 1

Question 2

What happens in 3rd step of pancreatic emrbryology?

Answer 2

Question 3

What is the major pancreatic vessel? And what does it join up with?

Answer 3

major papilla

joins with distan commone bile duct to form papilla ampulla

Question 4

Describe structure of pancrease?

Answer 4

head, neck, body, tail

Question 5

Find the pancreas on this CT scan?

Answer 5

Question 6

what type of imagery is this?

Answer 6

Question 7

What is difference between endocrine and exocrine secretions?

Answer 7

endocrine - into blood stream, effect on distant target organ, ductless glands

exocrine - into duct have direct local effect?

Question 8

Main endocrine secretions of pancreas?

Answer 8

insulin - anabolic

glucagon

somatostatin - endorcrine cyanide

Question 9

Where is endocrine area of pancrease + how much of % of pancrease?

Answer 9

islets of langerhans

2

Question 10

What is function of exocrine part of pancreas?

Answer 10

98%

secretess pancreatic juice into duodenum via sphincter of oddi/ampulla

digestive function

Question 11

What are acinin?

Answer 11

ducts, grap like clusters of secretory units

acinar cells secrete pro enz into ducts

Question 12

What are islets?

Answer 12

derived from brahncing duct

loose contact with ducts

differentiate into a and b cells secret into blood

more of them in tail than head

Question 13

What is organisation of pancreatic microanatomy?

identify acinar and islets of langerhans

Answer 13

Question 14

Label histologt of islet?

Answer 14

Question 15

Label acini

Answer 15

Question 16

What are 2 components of pancreatic juice

and which 2 cells produce each one?

Answer 16

Question 17

How is bicarbaronate juice produces?

what is its function(2)?

Answer 17

Question 18

What is relationship between dunodenal pH and bicarbonate secretions?

Answer 18

Question 19

Why does HC03- secretions stop when pH is still acidic?

Answer 19

Question 20

What is mechanism of HC03 secretion (think C02)?

Answer 20

Question 21

What happens to HC03- produced in pancreatic duct cell?

Answer 21

Question 22

How is excess Na+ in panreactic cell dealt with?

Answer 22

Question 23

How are K+ and Cl- levels in pancreatic cell balanced out?

Answer 23

Question 24

How is what happens in pancreatic cell similar to gastric parietal cells?

Answer 24

Question 25

Where are enzymes for digestion stored and syntehied?

Answer 25

in zymogen granules in acinar cell

Question 26

What is a zymogen?

Answer 26

pro enzyme

Question 27

What preventes the enzymes from possbiel causing damage to pancreas (4)?

Answer 27

Question 28

How are some proteoylic and soem lytic enzymes converted into active forms?

Answer 28

duodenal mucosa secrete enterkinase

Question 29

What do lipases additionally need? (2)

Answer 29

some require **colipase (precursor)** **p**resence of bile salts for effective actions

Question 30

what can lack of pancreatic enzymes cause?

Answer 30

can cause malnutrition even if diertay input is ok

Question 31

side effects from orlistat ( inhibte lipases)?

Answer 31

increase faecal fat, steatohrea

Question 32

what are 3 phases of pancreatic juice secretion?

Answer 32

cephalic gastric intestinal

Question 33

What happens in cephalic?

Answer 33

reflex to sight good causing enzyme rich compnent of acini only low volume , mobilisation enz

Question 34

what happens in gastric phase?

Answer 34

stimulation of pancreatic secretion of food in stomach same mechanism sa cephalic

Question 35

what happens in intestinal phase? how is it mediated? what is differnet about it?

Answer 35

hormnal mediated when gastric chyme enter duodenum BOTH components of pancreatic huice are stimulated HC03- AND enz flow in duodenum

Question 36

How in enz secretion of acini controlled?

Answer 36

Question 37

how is bicaronate secretion controlled in duct and centroacinar cells?

Answer 37

secretin (cAMP)

Question 38

how exactly does CCK control enzyme secretions in acini?

Answer 38

CCK is controlled by duodenal I cell CCK release is stimulated by fatty acid and Amino acid CCK is inhbited by trypsin

Question 39

What is important to consdier about acinar fluid?

Answer 39

It is isotonic - resembles plasma in its concs secretions of acinar fluid and protients it contains is stimulated by CCK

Question 41

What does the secretin cause?

Answer 41

secretions of H20 and HC03- from cells lining extralobular ducts

Question 42

Why is secretin stimulation secretions richer in HC03- than acinar secretions?

Answer 42

Due to Cl- and HC03 exhcnage

Question 43

how is HC03- controlled? (-ve feedback)

Answer 43

Question 44

What is important about CCK effect on HC30-?

Answer 44

no effect alone NEEDS stimulattion on secretin

Question 45

What effect does vagus nerve have?

Answer 45

similar effect to CCK

Question 46

What effect does secretin have on enzyme secretions?

Answer 46

NO EFFECT

Question 47

What happens when you eat a meal? starting with low pH stomach to how pH is lowered to enzyme release

Answer 47