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 Stroke Angina Myocardial infarction Pulmonary embolisms Deep 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 flow Release, First sound – systole No 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? Review