(22) AMY - PANCREATIC ENZYMES

Question 1

• Systematic name: a-1,4-glucan, 4-glucohydroalse
• Smallest enzyme in plasma (therefore it is normally filtered in glomerulus)
• Digestive enzyme that catalyzes the breakdown of starch & glycogen via α, 1-6 branching linkages
  o Specifically breaks down polysacchs

Answer 1

Amylase

Question 2

Amylase Major tissue sources:

Answer 2

Pancreas, Salivary gland

Question 3

Amylase Minor tissue sources:

Answer 3

Adipose tissues, Small Intestine, Skeletal muscles, Fallopian tube

Question 4

acute pancreatitis, renal failure & parotitis (parotid gland is a major salivary gland)

Answer 4

Pathologic ↑ AMS:

Question 5

Amylase is used in the diagnosis of acute pancreatitis: rises ____ after the attack, peaks at ___, and normalizes after ____.

Answer 5

Amylase is used in the diagnosis of acute pancreatitis: rises 2-12 hrs after the attack, peaks at 24 hours, and normalizes after 3-5 days.

Question 6

fastest to elevate after onset of attack in px w/ acute pancreatitis

Answer 6

Amylase

Question 7

↑plasma AMY = ↑Urine AMY

(how long in urine? Remains elevated for up to 7 days).

Answer 7

Acute pancreatitis

Question 8

↑plasma AMY = ↓urine AMY

Normally excreted substances cannot be excreted in urine in pxs w/ renal dsz.

Answer 8

Renal dsz

Question 9

Note:

Answer 9

Despite the quick elevation in acute pancreatitis, AMY is still not specific to AP.

Question 10

Salivary Amylase:

Answer 10

Ptyalin (fast moving)

Question 11

Pancreatic Amylase:

Answer 11

Amylopsin (slow moving)

Question 12

Measures the disappearance of starch substrate

Answer 12

Amyloclastic

Question 13

Amyloclastic

AMY activity is inversely proportional to absorbance of the test.
↑AMY activity = ↓color rxn (vice versa) = ↓absorbance reading

Answer 13

Substrate: Starch

Starch-Iodine Complex (Dark-blue) → ↓in color intensity
* Alternative substrate if no starch: lipogen
Iodine + lipogen = mahogany brown product

Question 13

• Measures the appearance of the product
• Measurement of reducing sugar is directly proportional to the activity of AMY to the polysacc substrate

Answer 13

Saccharogenic

Starch → reducing sugars (ex. glucose)

Question 14

• Measures the increasing color from production of product – chromogenic dye fragment
• AMY activity is directly proportional w/ the absorbance

Answer 14

Chromogenic

Insoluble starch-dye → soluble starch-dye fragments

Question 15

Coupling of several enzyme systems to monitor amylase activity

Answer 15

Continuous monitoring

Question 16

Assay for enzyme activity of AMY:

(refer to handout page 12)

Answer 16

o ↑absorbance @340nm is measured
o Measures the ↑absorbance of NADH (reduced)
o Primary enzyme: AMY
o Coupling enzyme: a-glucosidase, hexokinase, G6PD