Drug pathways

Question 1

Thiazide diuretics e.g. bendroflumethiazide

Answer 1

Blocks NaCl reabsorption at the distal tubule in the kidneys by blocking the NaCl co-transporter

Question 2

Loop diuretics e.g. furosemide

Answer 2

Inhibits Na reabsorption in the loop of Henle

Question 3

Potassium sparing diuretics e.g. spironolactone

Answer 3

Blocks the action of aldosterone

Question 4

Bisoprolol

Answer 4

Block B1 adrenoreceptors antagonising the sympathetic nervous system

Question 5

Atenolol

Answer 5

Blocks B1 and B2 adrenoreceptors

Question 6

Ca2+ channel blockers e.g. amlodipine

Answer 6

Binds to L-type Ca2+ channels in smooth muscle causing relaxation

Question 7

Nitrates e.g GTN or Isosorbide

Answer 7

metabolism releases nitric oxide dilating vascular smooth muscle and reducing preload to the heart

Question 8

Potassium channel openers e.g. nicorandil

Answer 8

Vasodilator

Question 9

Ivabradine

Answer 9

Lowers HR

Question 10

Aspirin

Answer 10

Blocks cyclo-oxygenase enzyme preventing the production of thromboxane A2

Question 11

Clopidogril

Answer 11

Blocks ADP binding to its receptor on platelet blocking platelet aggregation

Question 12

Heparin

Answer 12

Inactivates thrombin and activated factor x by biding to antithrombin

Question 13

Low molecular weight heparin e.g. Dalteparin

Answer 13

forms a complex with antithrombin converting it into an inactivator of factor Xa

Question 14

Streptokinase

Answer 14

Binds to circulating plasminogen to form an activator complex that converts further plasminogen to plasmin

Question 15

Class IA anti-arrhythmic drugs e.g. procainamide

Answer 15

dissociated from Na channels at a moderate rate

Question 16

Class IB anti-arrhythmic drugs e.g. Lidocaine

Answer 16

dissociates from Na channels at a rapid rate

Question 17

Class IC anti-arrhythmic drugs e.g. Flecainide

Answer 17

dissociates from Na channels at a rapid rate

Question 18

Class II anti-arrhythmic drugs e.g. propranolol

Answer 18

B-adrenoreceptor antagonist - decreases rate of depolarisation

Question 19

Class III anti-arrhythmic drugs e.g. amiodarone

Answer 19

Voltage activated K+ channels - prolong AP duration increasing refractory period

Question 20

Class IV anti-arrhythmic drugs e.g. verapamil

Answer 20

voltage activated Ca2+ channels - slow conduction in SA and AV nodes

Question 21

Class V anti-arrhythmic drugs e.g. adenosine

Answer 21

activates A1-adenosine receptors coupled to Gi, opens ACh sensitive K+ channels (GIRK)

Question 22

Adrenaline

Answer 22

increases contractility, HR, dilates coronary arteries and redirects blood flow away from the gut and skin