Atherosclerosis process ...      

 

By 

Enzyme needed and product in thrombosis    

By 

3 CVD conditions     

By 

3 hormones involved in glucose regulation       

 By

Sphygomamo-meter procedure and sound during systole/ diastole      

By

Atherosclerosis process ... Damage endothelium

Inflammatory response

Plaque formation

Raised BP

 

Enzyme needed and product in thrombosis Thrombin convert fibrinogen into fibrin (insoluble)   

 

3 CVD conditions  StrokeAnginaMyocardial infarctionPulmonary embolismsDeep vein thrombosis

Not Diabetes (glucose) 

3 hormones involved in glucose regulation   Insulin (high)Adrenalin (fight /flight – inhibit insulin, stimulate glucagen)Glucagon (low)   

 

Sphygomamo-meter procedure and sound during systole/ diastole Inflates cuff to stop blood flowRelease, First sound – systoleNo sound diastole

BIG PICTURE

Content Explain what cholesterol is and why it is needed Compare and contrast the 2 transport systems for

cholesterol. Analyse the treatments available for cholesterol

Process Video clip and data analysis

Benefit Make up your own mind ....

Higher blood cholesterol level = higher risk of heart disease Most cholesterol is synthesised by the liver from saturated

fats in the diet.

BUT the body does need cholesterol (steroids – for hormones etc. and cell membranes)

Insoluble cholesterol must combine with proteins to form soluble LIPOPROTEINS to be transported in blood

Two major transport lipoproteins:◦ HIGH DENSITY LIPOPROTEINS (HDLs)◦ LOW DESNITY LIPOPROTEINS (LDLs)

Main cholesterol carriers in blood, transports cholesterol made by liver to body cells.

Body cells have LDL receptors When LDL-cholesterol complex attaches it is

engulfed and then used by cell

Once body cell has sufficient cholesterol – negative feedback triggered which inhibits the synthesis of new LDL receptors.

So less taken up by body cells, so left circulating

Instead some taken in by endothelial cells. Cholesterol deposited in artery walls instead LDLs associated with formation of plaques

More likely if diet rich in saturated fats or genetic condition of hypercholesterolaemia

HDLs transport cholesterol from body tissues to liver to be broken down

Prevents high level of chloesterol build uo in blood stream (lowers blood cholesterol levels and helps remove plaque, so not contribute to atherosclerosis)

HDL known as ‘good cholesterol’ However a balance of HDL and LDL required

Normal chloesterol carried by ;◦ HDL – 20-30%◦ LDL – 60-70%

A higher ratio of HDL to LDL will result in lower blood cholesterol and a reduced chance of atherosclerosis.

Reverse is also true ......

Compare and contrast HDL and LDL

Regular physical activity tends to raise HDL levels

Dietary changes aim to reduce the levels of total fat in the diet and to replace saturated with unsaturated fats

“Mediterranean” diet idea Total less fat too!

Pair up A and B

A have 5 books and decide what to teach on statins

B have 5 books and teach on familial hypercholesterolaemia

Link the pedigree charts from reproduction to this topic

Research Familial hypercholesterolaemia What type of disorder?

(dominant/recessive / sex-linked) Any treatments?

Main drug type are called “statins”

Read p183 and explain what they do, how they work and their success rate.

Statins work in 2 ways ◦ First way - is to increase LDL receptors ◦ Second way – competitive inhibition with an enzyme

which makes cholesterol (statin competes with active site thus not allowing original molecule to enter – so overall decreasing the amount of cholesterol).

◦ Statins reduce blood cholesterol by inhibiting the synthesis of cholesterol by liver cells

LDL receptors are decreased Untreated – large cholesterol

Treatments; Modification of diet- reducing fats and oils Medication – statins

Extreme – filtration of blood

Most cholesterol is synthesised by the liver from saturated fats in the diet.

Cholesterol is a component of cell membranes and a precursor for steroid synthesis.

High-density lipoprotein (HDL) transports excess cholesterol from the body cells to the liver for elimination. This prevents accumulation of cholesterol in the blood.

Low-density lipoprotein (LDL) transports cholesterol to body cells.

Most cells have LDL receptors that take LDL into the cell where it releases cholesterol.

Once a cell has sufficient cholesterol a negative feedback system inhibits the synthesis of new LDL receptors and LDL circulates in the blood where it may deposit cholesterol in the arteries forming atheromas.

A higher ratio of HDL to LDL will result in lower blood cholesterol and a reduced chance of atherosclerosis.

Regular physical activity tends to raise HDL levels, dietary changes aim to reduce the levels of total fat in the diet and to replace saturated with unsaturated fats.

Drugs such as statins reduce blood cholesterol by inhibiting the synthesis of cholesterol by liver cells.

Question?? Answer

LDL

HDL

Statin

Lower / less LDL receptors

What was the question?

ReviewReview