PHR 912: KT15 EXAM WITH
COMPLETE SOLUTION
What is the "good" cholesterol? - ANSWER HDL
What is the "bad" cholesterol? - ANSWER LDL
LDL is produced from what other lipoproteins? - ANSWER -VLDL
-IDL
Why is HDL considered "good" cholesterol? - ANSWER Because it can take up
cholesterol and convert it to cholesteryl esters, which are then returned to the liver
Why is HDL high density? - ANSWER -More proteins
-Less triacylglycerols
HDL transfers what to chylomicrons? - ANSWER -ApoCII
-ApoE
What is the role of ApoCII? - ANSWER stimulates the degradtion of triacylglycerols
What is the role of ApoE? - ANSWER is a ligand for the liver receptor for
chylomicron-remnants and HDL
What is the role of ApoA1? - ANSWER stimulates LCAT to form cholesteryl esters
Where is ApoA1 located? - ANSWER on HDL
Whenever HDL becomes large due to uptake of cholesterol and triacylglycerols, what
can happen? - ANSWER The HDL can exchange triacylglycerols or phospholipids with
VLDL by using CETP
What is CETP? - ANSWER Cholesterol ester transfer protein
What are CETP inhibitors? - ANSWER inhibitors of CETP
What was the main idea behind CETP inhibitors (before them suckers failed)? - ANSWER
To raise HDL levels
What are some examples of failed CETP inhibitors? - ANSWER -Anacetrapib
-Dalcetrapib
, -Evacetrapib
Regarding CETP inhibitors, if HDL can no longer transfer with VLDL, what is the result? -
ANSWER HDL will transfer cholesteryl esters back to the liver, and it cannot uptake any
surface cholesterol, meaning that the liver will have to make MORE HDL in order to
compensate
Which statement is wrong about lipoproteins?
A) The density of the lipoproteins increases along with the unloading of triacylglycerols
B) HDL has the highest density due to its high contents of proteins
C) The major function of VLDL is to transport cholesterol to target tissue
D) VLDL is the lipoprotein that transports fats synthesized in the liver
E) HDL is also called "good cholesterol" - ANSWER C
What is the process of LDL formation? - ANSWER -VLDL is degraded to IDL
- IDL is degraded to LDL
-VLDL transfers both ApoE AND ApoC-II to HDL
What is the initial composition of VLDL? - ANSWER -ApoE
-ApoB100
-ApoC-II
-Triglycerides
-Cholesterol
After VLDL loses ApoC-II and ApoE, what remains? - ANSWER Just ApoB100, which is
the composition of LDL
LDL has a ____ content of triacylglycerols and a ____ content of cholesteryl esters. -
ANSWER -low
-high
LDL and IDL can be endocytosed by what organ? - ANSWER Liver
Additionally, LDL can be taken up by? - ANSWER Peripheral tissues
What is the purpose of LDL be endocytosed by peripheral tissues? - ANSWER To
supplement them with cholesterol
What is the "most important" lipoprotein receptor? - ANSWER LPL receptor
COMPLETE SOLUTION
What is the "good" cholesterol? - ANSWER HDL
What is the "bad" cholesterol? - ANSWER LDL
LDL is produced from what other lipoproteins? - ANSWER -VLDL
-IDL
Why is HDL considered "good" cholesterol? - ANSWER Because it can take up
cholesterol and convert it to cholesteryl esters, which are then returned to the liver
Why is HDL high density? - ANSWER -More proteins
-Less triacylglycerols
HDL transfers what to chylomicrons? - ANSWER -ApoCII
-ApoE
What is the role of ApoCII? - ANSWER stimulates the degradtion of triacylglycerols
What is the role of ApoE? - ANSWER is a ligand for the liver receptor for
chylomicron-remnants and HDL
What is the role of ApoA1? - ANSWER stimulates LCAT to form cholesteryl esters
Where is ApoA1 located? - ANSWER on HDL
Whenever HDL becomes large due to uptake of cholesterol and triacylglycerols, what
can happen? - ANSWER The HDL can exchange triacylglycerols or phospholipids with
VLDL by using CETP
What is CETP? - ANSWER Cholesterol ester transfer protein
What are CETP inhibitors? - ANSWER inhibitors of CETP
What was the main idea behind CETP inhibitors (before them suckers failed)? - ANSWER
To raise HDL levels
What are some examples of failed CETP inhibitors? - ANSWER -Anacetrapib
-Dalcetrapib
, -Evacetrapib
Regarding CETP inhibitors, if HDL can no longer transfer with VLDL, what is the result? -
ANSWER HDL will transfer cholesteryl esters back to the liver, and it cannot uptake any
surface cholesterol, meaning that the liver will have to make MORE HDL in order to
compensate
Which statement is wrong about lipoproteins?
A) The density of the lipoproteins increases along with the unloading of triacylglycerols
B) HDL has the highest density due to its high contents of proteins
C) The major function of VLDL is to transport cholesterol to target tissue
D) VLDL is the lipoprotein that transports fats synthesized in the liver
E) HDL is also called "good cholesterol" - ANSWER C
What is the process of LDL formation? - ANSWER -VLDL is degraded to IDL
- IDL is degraded to LDL
-VLDL transfers both ApoE AND ApoC-II to HDL
What is the initial composition of VLDL? - ANSWER -ApoE
-ApoB100
-ApoC-II
-Triglycerides
-Cholesterol
After VLDL loses ApoC-II and ApoE, what remains? - ANSWER Just ApoB100, which is
the composition of LDL
LDL has a ____ content of triacylglycerols and a ____ content of cholesteryl esters. -
ANSWER -low
-high
LDL and IDL can be endocytosed by what organ? - ANSWER Liver
Additionally, LDL can be taken up by? - ANSWER Peripheral tissues
What is the purpose of LDL be endocytosed by peripheral tissues? - ANSWER To
supplement them with cholesterol
What is the "most important" lipoprotein receptor? - ANSWER LPL receptor
