Blood Cholesterol Determination (M)

Question 1

What are the purposes of blood cholesterol determination?

Answer 1

1) To check risks of coronary heart disease
2) To assess the effectiveness of medications and
3) To serve as a preventive measure to check any risks depending on factors like eating habits, diet, stress, exercise and life-style related

Question 2

What are the tests that are included in lipid profile test?

Answer 2

1) HDL cholesterol
2) LDL cholesterol
3) Triglycerides
4) Total Cholesterol

Question 3

What is HDL cholesterol?

Answer 3

It is the amt of good cholesterol that helps to prevent heart diseases

Question 4

What is LDL cholesterol?

Answer 4

It is the measurement of bad cholesterol that causes heart diseases by clotting blood arteries

Question 5

How does LDL cholesterol cause heart diseases?

Answer 5

By clotting arteries

Question 6

What are triglycerides?

Answer 6

It is the measurement of all triglycerides in the lipoproteins

Question 7

What is total cholesterol?

Answer 7

It is the accurate amt of complete cholesterol in the blood

Question 8

What are the characteristics and purposes of cholesterol?

Answer 8

1) It is a necessary component of cells and body fluids
2) It plays a major role in manufacturing and repairing cell membranes and in the synthesis of bile acids
3) It activates vit D
4) It serves as a precursor of steroid hormones

Question 9

Provide an ex of steroid hormone

Answer 9

Estrogen

Question 10

What is the purpose of estrogen?

Answer 10

It is the hormone that controls the transport and excretion of cholesterol

Question 11

What is the sx consideration for blood chole determination (in terms of sx collection)?

Answer 11

In sx collection, fasting of 8-10 hrs is necessary

Question 12

What is the sx consideration (in terms of suitable sxs for blood chole determination)?

Answer 12

Serum, heparinized, or EDTA plasma are suitable sxs

Question 13

What is the sx consideration (in terms of stability of the sx) for blood chole determination?

Answer 13

Stability: for 7 days at 20-25 DC; for 3 mos at -20 DC

Question 14

What is the sx consideration (in terms of sx usage) in blood chole determination?

Answer 14

Avoid using hemolyzed serum especially in colorimetric methods

Question 15

Is it okay to use hemolyzed sxs? If yes, at what certain test/s? If no, at what certain test should it not be used?

Answer 15

No, especially in colorimetric methods

Question 16

What is the sx consideration (in terms of equipment that will be used) in blood chole determination?

Answer 16

Use clean and dry test tubes during processing

Question 17

What are the mats needed for blood chole determination?

Answer 17

1) Complete blood collection set
2) Three 5 mL clean and dry test tubes
3) Test tube rack
4) Automatic pipettors
5) Pipette tips
6) Parafilm
7) Spectrophotometer cuvettes
8) Tissue

Question 18

What is the process employed in blood chole determination?

Answer 18

Cholesterol Oxidase-Peroxidase

Question 19

What is the principle of Cholesterol Oxidase-Peroxidase?

Answer 19

Determination of chole after enzymatic hydrolysis and oxidation. The colorimetric indicator is quinoneimine w/c generated from 4-aminoantipyrine (4-aap) and phenol by hydrogen peroxide under the catalytic action of peroxidase

Question 20

What is the colorimetric indicator used in cholesterol oxidase-peroxidase?

Answer 20

Quinoneimine

Question 21

Where (or how) is quinoneimine generated?

Answer 21

It is generated from 4-aminoantipyrine (4-aap) and phenol by H2O2 under the catalytic action of peroxidase

Question 22

What is the principle (or formula) of cholesterol oxidase-peroxidase?

Answer 22

Cholesterol ester -> via the action of CE -> Cholesterol -> via the action of CO; O2 becomes H2O2 + phenol + 4-AAP (via the action of PO, quinoneimine is produced) -> Cholestenone (produced right after the action of CO)

Question 23

What is the process (or lab steps) of blood chole determination?

Answer 23

1) Prepare and inspect the rgnt
2) Prepare the ff tubes and add the chole rgnt
a. Blank (1000 uL)
b. Std (1000 uL)
c. Sx (1000 uL)
3) Add the ff rgnts to your test tubes
a. Blank (10 uL; distilled H2O)
b. Std (10 uL)
c. Sx (10 uL)
4) Mix and incubate
5) Read and record the absorbance at 520 nm
Via the use of either:
a. Spectrophotometer
b. Semi-automated analyzer

Question 24

What is the reference range for blood chole determination?

Answer 24

Risk classification

1) Desirable
2) Borderline
3) High

Total Cholesterol in Blood (mg/dL)

1) < 200
2) 200 - 239
3) > or equal to 240

Question 25

What is the unit used for blood chole determination?

Answer 25

mg/dL