Cardiovascular And Renal Pharmacology

Question 0

Altepase

Answer 0

Serine protease - catalyses the conversion of plasminogen to plasmin. Helps clot breakdown - localised action. Myocardial infarction and acute ischaemic stroke.

Question 1

Acetazolamide

Answer 1

Carbonic anhydrase inhibitor. Weak diuretic to treat oedema. Now more to treat glaucoma.

Question 2

Alpha-methylnoradrenaline

Answer 2

Selective A2 agonist. Inhibits sympathetic nervous system output and lower blood pressure. Antihypertensive.

Question 3

Amiloride

Answer 3

Blocks ENaC - inhibits Na+ reabsorption, promotes H20 loss. Potassium sparing diuretic. Hypertension and congestive heart failure.

Question 4

Aminocaproic acid

Answer 4

Lysine analogue. Effective inhibitor for enzymes that bind to that it. Including plasmin (fibrinolysis). Treat excessive postoperative bleeding (eg. Cardiac surgery).

Question 5

Amiodarone

Answer 5

Class III antiarrhythmic agent - ventricular and atrial dysrhythmias. Prolongs phase III of the cardiac action potential (depolarisation phase). Very common use.

Question 6

Bisoprolol

Answer 6

Selective B1 blocker. Limit damaging effects of chronic catecholamine stimulation to improve cardiac function.

Question 7

Captopril

Answer 7

ACE inhibitor. Inhibits conversion of ATI to ATII. Prevents vasoconstriction and aldosterone secretion. Prevents increase in blood pressure.

Question 8

Clonidine

Answer 8

Centrally acting A2 agonist. Treat hypertension.

Question 9

Clopidogrel

Answer 9

Irreversibly binds to P2Y12 receptor on platelet cell membranes. Inhibits blood clots. Used in coronary artery disease, vascular disease and the prevention of myocardial infarction.

Question 10

Dabigatran

Answer 10

Thrombin inhibitor. Used in atrial fibrillation and stroke. Prophylactically to prevent thromboembolism.

Question 11

Digoxin

Answer 11

Cardiac glycoside. Inhibits Na/K/ATPase. Lots of Na+, Ca2+ cannot be pumped out so stronger contractions. Used to alleviate oedema and antidysrhythmias.

Question 12

Diltiazem

Answer 12

Calcium channel blocker. Potent vasodilator. Class IV antiarrhythmic. Hypertension, angina and some arrhythmias.

Question 13

Enalapril

Answer 13

ACE inhibitor. Prodrug, activated in the liver. Used in hypertension and in heart failure (decrease pre and after load)

Question 14

Eptifibatide

Answer 14

Inhibitor of glycoprotein IIb/IIIa receptor normally needed for fibrinogen bridging between platelets -> aggregation. Prevention of myocardial infarction.

Question 16

Furosemide

Answer 16

Loop diuretic - high ceiling as high rate of diuresis. Sulphonamides. Blocks the Na+-K+-2Cl- co trasporter in the apical membrane of the cells.Reduces reabsorption of these ions so water is drawn out and excreted. Also causes venodilation which reduces atrial filling pressure which increases renal blood flow withouth a change in GFR.

Question 17

Heparin

Answer 17

Naturally occuring anticoagulant produced by basophils and mast cells. Binds to enzyme inhibitor antithrobin III -> conformational change exposes active site. This inactivates thrombin and proteases involved in blood clotting (eg. Factor Xa). Used in unstable angine, myocardial infarction, deep vein thrombosis and prophylactic to prevent clots forming.

Question 18

Hydrochlorothiazide

Answer 18

Thiazide diuretics. Some inhbition of carbonic anhydrase Act on corical segment of TAL - block the Na+-Cl- cotransporter (binding to the Nl- site), reduceing reabsorption and increases water excreted. Also have vasodilatory effects. Hypokalaemia a problem

Question 19

Levosimendan

Answer 19

Inodilator (calcium snesitiser) used in hospitals for heart failure.Also has a vasodilatory effect by opening ATP-sensitive ptassium channels in vascular smooth muscle to cause smooth muscle relaxation. Increase force of contraction, decrease preload and afterload.

Question 20

Losartan

Answer 20

First non-peptide angiotensin II antagonist (angiotensin receptor blocker). Acts on the AT1 angiotensin II receptor - these are the receptors involved in normal response.

Question 21

Mannitol

Answer 21

Osmotic diuretic. Filtered in glomerulus but not reabsorbed, retain osmotic equivalent of waer so increase urine volume. Decrease Na+ reabsorption. Useful where urine flow is reduced. If used for a long time, screws up electrolyte balance. Used if want to get rid of a lot of fluid in a short space of time eg. cerebral oedema.

Question 22

Milrinone

Answer 22

Type III phosphodiesterase inhibitor is the mst often used inodilator in heart failure. Limited use as can cause dysrythmias. Short term treatment of severe heart fialure unresponsive to more conventional therapy.

Question 23

Minoxidil

Answer 23

Contains nitric oxide functional group so may act as a nitric oxide agonist. Also a potassium channel opener (KCO) - acts on ATP-sensitive K+ channels in vascular smooth muscle -> causing hyperpolarisation of cell membranes and relaxation. Antihypertensive vasodilatory medication, can be used to treat severe refractory hypertension. Slows/stops/promotes hair regrwoth. Treatment of androgenic alopecia.

Question 24

Ouabain

Answer 24

Also a Na+-K+ pump inhibit causing the Na+ gradient to decrease and therefore unable to pump Ca2+ out of cardiomyocytes so stronger contractions. Too powerful for clinical use but used experimentally.

Question 25

Pimobendan

Answer 25

Calcium sensitiser - snesitise and increase the cardiac Ca2+ binding efficiency to troponin without a requirement for more energy consumption. Cause peripheral vasodlatation by inhibiting PDEII. Veterinary used.

Question 26

Propranolol

Answer 26

Non-selective beta blocker. Used to treat hypertension, angina, myocardial infarction etc.

Question 27

Reserpine

Answer 27

Depletes catecholamines from peripheral sympathetic nerve endings Blocks the VMAT so neurotransmitters can’t be transported into vesicles or released. Long lasting effects.

Question 28

Rivaroxaban

Answer 28

Factor Xa inhibitor - prevent clotting, atrial fibrillation and stroke patients.

Question 29

Saralasin

Answer 29

Angiotensin II receptor partial agonist - peptide socan’t be given orally. IV administration.

Question 30

Sildenafil

Answer 30

(Viagra). Phosphodiesterase V inhibitor (cGMP specific). AN inodilator , by increase intracellular levels this mimics the effects of B-receptor stimulation. Vasodilatation decreases the after load on the heart.

Question 31

Streptokinase

Answer 31

Binds to plasminogen activator and causes generation of plasmin - leads to degradation of the fibrin in cloths and also breaksdown clotting factors II, V and VII.

Question 32

Tirofiban

Answer 32

Antiplatelet drug - glycoprotein Iib/IIIa inhibitors - which is needed for fibronigen bridging between platelets that causes aggregation. Used for prevention of myoardial infarction.

Question 33

Tranexamic Acid

Answer 33

Analogue of aminocaproic acid so competitively inhibits plasminogen activation. Used to prevent excessive clot lysis which could lead to severe bleeding.

Question 34

Triamterene

Answer 34

Potassium sparing diuretic used in combinationiwth thiazide diuretics for the treatment of hypertension and oedema. Blocks the ENaC - increases concentration of Na+ in the urine without affecting K+ too much.

Question 35

Warfarin

Answer 35

Orally given clot inhibitor. Inhibits synthesis of clotting factors II, VII, IX and X and regulation factors - protein C, S and Z. Prophylactic and also prevent clot formation on prostehtic heart valves.