pharmacology

Question 1

How do aquaretics reduce preload?

Answer 1

Vasopressin (ADH) receptor antagonists

Question 2

where does gentomycin act in the kidney

Answer 2

on the apical membrane of the proximal tubule

Question 3

clinical uses of osmotic diuretics

Answer 3

raised intracranial P intraoccular P prevention of acute renal tailure

Question 4

clinical use of spironolactone

Answer 4

in combination with loop or thiazide diuretics heart failure hyperaldosteronism

Question 5

how do aldosterone receptor antagonists reduce preload?

Answer 5

Inhibit aldosterone action on the cortical and distual tubules of the nephron (K+ sparing - monitor for hyperkalaemia)

Question 6

adverse effects of loop diuretics

Answer 6

hypokalemia metabolic alkalosis hypovolaemia hypotension

Question 7

adverse effects of spironolactone

Answer 7

hyperkalemia GI upset

Question 8

where do the 4 types of diuretics act?

Answer 8

loop diuretics - ascending limb of loop of henle

thiazide diuretics - distal tubule

K+ sparing diuretics - collect duct

osomotic diuretics - mainly proximal tubule

Question 9

onset and duration of triamterene and amiloride

Answer 9

tiamterene: onset - 2hours, duration 12-16hrs amilordie: onset: slow, duration 24 hours

Question 10

furosemide is what kind of drug

Answer 10

Diuretic

Question 11

clinical use for loop diuretics

Answer 11

salt and water overload hypertension

Question 12

distal consequence of loop diuretics

Answer 12

increases the osmotic P in the distal tubule –> reducing water reabsorption in distal tubule

Question 13

mechanism of diuretics

Answer 13

increase Na and water excretion from kidney lowering blood volume and blood pressure

Question 14

mechanism of action of gentomycin toxicity on the kiney

Answer 14

bins to phsopholipids and effects calcium levels –> effects mitochondria –> cell damage –> apoptosis

Question 15

mechanism of action of spironolactone

Answer 15

acts as an aldosterone R antagonist - decreases activation of Na channels in the Collecting duct - decreases the stimulation of Na pump synthesis this reduces osmotic P and therefore reduces water reabsorption

Question 16

What is “The Triple Response”?

Answer 16

The actions of histamine: Reddening - due to vasodilatation at initiating site Wheal - due to increased vascular permeability (localised oedema response) Flare - spreading response through the sensory fibres

Question 17

How do diuretics reduce preload

Answer 17

Act on the loop of Henle to decrease Na and Water reabsorption –> increase urine output –> decrease blood volume

Question 18

onset and half life of spironolactone

Answer 18

slow onset short half life of 10 mins, but metabolite longer half life of 16 hours

Question 19

mechanism of action of osmotic diuretics

Answer 19

decrease the passive reabsorption of water, with only a small decrease in Na reabsorption

Question 20

3 types of drugs that can act on kindeys

Answer 20

1) diuretics 2) drugs that alter pH of urine 3) drugs that alter secretion of organic molecules

Question 21

4 types of diuretics?

Answer 21

loop diuretics thiazide duiretics osmotic diuretics postassium sparing diuretics

Question 22

mechanism of action of thiazide diuretics

Answer 22

inhibit the Na/Cl cotransporter in the distal convuluted tubule –> decreasing the osmotic P and therefore reducing water reabsorption

Question 23

loop diuretics - mechanism of action

Answer 23

the Na/K/Cl carrier in the ascending limb of the loop of henle –> decreases the hypertonicity in the interstitium, decreasing osmotic P and therefore reduces water reabsorption

Question 24

what are the effects of gentomycin kidney toxicity

Answer 24

proteinuria

decreased GFR

altered concentrating ability

Question 25

where do antineoplastics act in the kidney

Answer 25

acts in the distal tubule and collecting duct