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Year 2 - GI System > Digestion > Flashcards

Flashcards in Digestion Deck (29):
1

Which pancreatic enzymes are secreted in their active form?

Amylase
Colipase
Lipase

2

List the enzymes secreted by the pancreas.

Amylase
Colipase
Lipase
Chymotryspinogen
Trypsinogen
Carboxypeptidase
Elastase
RNAase
DNAase
Cholesterol ester enzyme
Bicarbonate

3

What is a zymogen?

A collection of pro enzymes secreted from the pancreas along with enzyme inhibitiors.

4

What activates trypsinogen in the duodenum?

Enterokinase

5

Name two endopeptidases.

Chymotrypsin
Trypsin
Pepsin

6

What is an endopeptidase?

A proteolytic peptidase that break the bonds of non-terminal amino acids in a peptide chain.

7

Describe the two molecular forms which starch can take.

Amylose - non-branched, with only alpha 1-4 glycosidic bonds
Amylopectin - branched, with the main chain connected by 1-4 bonds, and the branches connected by 1-6 branches.

8

Is amylose or amylopectin harder to digest and why?

Amylose - because it's unbranched, it's packed tighter, and it's harder for the amylase to reach the bonds

9

What are the normal products of starch digestion?

Disaccharides
Oligosaccharides

10

What carbohydrates are digested at the brush border?

Disaccharides
Oligosaccharides
Sucrose
Maltose
Lactose

11

What happens to starch that isn't digested in the small intestine?

It passes into the large intestine where it is digested by colonic bacteria.

12

Give a brief description of acute pancreatitis.

An acute inflammatory disease in which pancreatic enzymes digest the gland.

13

What are some of he possible causes of acute pancreatitis?

ALCOHOL
GALL STONES
Infection
Trauma
Certain drugs

14

Describe the pathological mechanism of acute pancreatitis.

The way in which it begins is unknown, but it ends in the activation of trypsin.
This activates all the other pancreatic enzymes, which start to digest the gland.
Inflammatory mediators travel here and cause a local inflammatory response.
- can be systemic response in the severe cases

15

Give a brief description of chorionic pancreatitis.

It's a chronic inflammation of the pancreas - destroying both the exocrine and endocrine functions.

16

What are the presenting complaints of chronic pancreatitis?

Weight loss (due to malabsorption)
Diabetes mellitus
Acute abdominal pain
Steatorrhea

17

What are some of the symptoms of acute pancreatitis?

Sudden onset abdominal pain
Nausea and vomiting
Fever
Hypotension
Shock
Multi-organ failure

18

What are the biochemical findings you would expect in acute pancreatitis?

Increased amylase
Increase lipase
Increase urea
Decreased albumin
Decreased calcium
Increased triglycerides

19

What are the most common causes of chronic pancreatitis?

Alcohol abuse
Repeated attacks of acute pancreatitis
Hereditary
Trauma
Hypercalcaemia
Idiopathic
Tropical

20

What are the tests of pancreatic function?

Faecal chymotrypsin
Faecal elastase

21

How long does elevated serum amylase last in acute pancreatitis?

It rises within 5-8 hours of onset and lasts for roughly 4 days.

22

Is amylase a good test for acute pancreatitis, and why?

No - because it is low specificity
It can also be a sign of
- other intra-abdominal disease
- DKA
- renal insufficiency
- tumours
- drugs
- salivary gland lesion

23

What is the what does a high serum amylase, but a low urine amylase level mean?

Macroamylasaemia
-if they are both high, then it is more likely to be acute pancreatitis

24

What happens to serum lipase in acute pancreatitis, and what are the benefits of measuring this over amylase?

It peaks within 24hrs and return to normal within 8-14 days
It is more specific and sensitive to acute pancreatitis than amylase measurements

25

What is the difference between direct and indirect pancreatic function tests for pancreatitis?

Direct test are invasive
Indirect tests are on blood, urine or faeces

26

Name the two direct pancreatic function tests.

1) Secretin-pancreozymin test (measures pancreatic enzymes in the duodenum) -GOLD STANDARD
2) Lundh test - measures [bicarb], amylase or trypsin activity following a meal

27

What two enzymes can you test for in faeces?

Cymotrypsin
Elastase

28

Describe the two faecal tests.

Chymotrypsin
- measured in faeces
- low value indicates pancreatic insufficiency
Elastase
- not degraded during passage through the intestines
- low value indicated pancreatic insufficiency

29

Which bonds in starch does amylase break?

Alpha 1-4 glycosidic bonds