Hepatic

Question 1

how many lobes does the liver consist of ?

Answer 1

two

Question 2

what are the lobes dividied by ?

Answer 2

the hepatic vein

Question 3

where is the liver located ?

Answer 3

upper right corner of the abdomen

Question 4

hepatic artery ?

Answer 4

supplies 25% of the total blood flow and provides most of the oxygen. This is coming from the heart.

Question 5

portal vein ?

Answer 5

drains most of the gastrointestinal tract (GI). It supplies 75% of the blood flow and transports the most recently absorbed material from the intestines to the liver.This comes from the intestines.

Question 6

what does the liver store ?

Answer 6

glycogen, vitamins and iron.

Question 7

the liver contains an extensive reticuloendothelila system , why ?

Answer 7

for the synthesis and breakdown of blood cells.

Question 8

what’s the primary function of the liver cells ?

Answer 8

metabolize, detoxify and excrete both endogenous and exogenous compounds (first pass metabolism). This will include metabolism and excretion of drugs and toxins

Question 9

describe cholesterol ?

Answer 9

waxy , fat like substance that is a sterol , steroid alcohol. It is found in all cells of the body as it is part of the lipid bilayer.

Question 10

how is cholesterol in the body ?

Answer 10

75% of the cholesterol is synthesised and the other 25% comes from our diet.

Question 11

where does cholesterol synthesis mainly occur ?

Answer 11

liver , cytoplasm and the ER

Question 12

what is the rate limiting step of cholesterol synthesis ?

Answer 12

HMG-CoA reductase reaction is the rate limiting step as it is at the start of the reaction.

Question 13

what step does pharmacological intervention occur at and give an example ?

Answer 13

the HMG - CoA reductase stage , statins

Question 14

what hormones are cholesterol part of ?

Answer 14

sex hormones such as testosterone , hormones released by the adrenal gland.

Question 15

how is the bile acids and cholesterol involved?

Answer 15

cholesterol is required for production and bile acids used for neutralisation

Question 16

describe atheroscelerosis ?

Answer 16

formation of fatty plaques in the blood vessels and they can lead to heart attacks , strokes , angina and an increased risk of coronary heart disease. This is due to a narrowing of the artery and this causes an abnormal blood flow and oxygen delivery.

Question 17

risk factors ?

Answer 17

diet , medical conditions such as diabetes and hypertension. Genetics , sex , age , smoking and inactivity and obesity.

Question 18

what are chylomicrons ?

Answer 18

small fat globules composed of protein and fat.

Question 19

if a person is suffering from high cholesterol levels what will the ratio of lipoproteins be ?

Answer 19

LDL will be high. The ratio of HDL:LDL is important in cholesterol levels.

Question 20

what are aplolipoproteins?

Answer 20

proteins that bind lipids

Question 21

how many classes are there ?

Answer 21

6

Question 22

ApoA-I ?

Answer 22

synthesised in the liver and intestines. They are structural in HDL and reverse cholesterol transport

Question 23

ApoA-V ?

Answer 23

synthesised in the liver and they modulate triglyceride incorporation into the hepatic VLDL

Question 24

ApoB-100 ?

Answer 24

synthesized in the liver and it is a structural portien of the VLDL , IDL and LDL

Question 25

ApoB-48 ?

Answer 25

synthesized in the intestine and it is a structural protein of chylomicrons

Question 26

ApoE ?

Answer 26

synthesized in the liver , brain , skin , gonads and spleen. It is a structural in HDL and they can reverse cholesterol transport

Question 27

why are statins used to treat hyperlipidemia ?

Answer 27

These work by decreasing the blood cholesterol and also lowering the risk of cardiovascular death. Statins works by increasing the ratio towards the HDL and lowering the LDL.

Question 28

mechanisms of statins ?

Answer 28

They inhibit an early and rate limiting step in cholesterol biosynthesis , the HMG-CoA reductase. This inhibits the hepatic cholesterol synthesis which results in an increased expression of the LDL receptor gene. This decreases the free cholesterol causes membrane-bound SREBPs to be cleaved and translocated to the nucleus to bind the sterol responsive element of the LDL receptor gene. This enhances transcription and increases the synthesis of LDL receptors. It also reduces the degradation of LDL receptors.

Question 29

statins on Rho and Rac

Answer 29

blocks Rho and Rac so this causes more eNOS to be produced and less of the reactive oxygen species NAP(P)H-ox

Question 30

statins on triglyceride levels ?

Answer 30

decrease them

Question 31

adverse effects of statins ?

Answer 31

Hepatotoxicity
• Elevated hepatic transaminase values
• One case of liver failure per million person-years of use
Myopathy
• One death per million prescriptions caused by rhabdomyolysis

Question 32

what are surrogate markers ?

Answer 32

not direct effects

Question 33

name some factors that lead to the fatty plaque formation ?

Answer 33

• Platelet activation
• Thrombotic effect as this leads to coagulation
• Platelet stability
• Vascular inflammation
• SMC hypertrophy
• Endothetlial dysfunction
• Proliferation
• Vasoconstriction

Question 34

JUPITER ?

Answer 34

Justification for the use of statins in primary prevention: an Intervention Trial Evaluating Rosuvastatin.

Question 35

what was it for ?

Answer 35

This was a randomised, double-blind, placebo-controlled primary prevention trial studying the patients without evidence of CVD.

Question 36

what did the treatment with Rosuvastatin do ?

Answer 36

lower LDL and risk of CVD and atherosclerosis progression.