ACE inhibitors, Angiotensin Receptors Inhibitors And Diuretics Flashcards

1
Q

What is the vascular endothelium and what are its functions?

A

A single layer of cells on the inner surface of blood vessels.

Barrier, clotting, angiogenesis, inflammation, vasoconstriction/vasodilation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What potent mediators does endothelium contain?

A

Vasodilators and vasoconstrictors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What does the renin-angiotensin-aldosterone system (RAAS) regulate?

A

Blood pressure, blood volume and electrolyte balance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Under what three circumstances would renin be released?

A
  • Reduced sodium delivery to distal convoluted tubule
  • Reduced perfusion pressure in the kidney
  • Sympathetic stimulation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What hormones are involved in the RAAS?

A
  • Atrial natriuretic Peptide (ANP)
  • Vasopressin/antidiuretic Hormone (ADH)
  • Aldosterone
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What protease Enzymes are involved in the RAAS?

A

Wouldn’t you like to know cowboy 🤠

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is Angiotensin 2?

A

An active octapeptide that is a potent vasoconstrictor which increases blood pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What does Renin and ACE convert?

A

Renin - Angiotensinogen to Angiotensin 1
ACE - Angiotensin 1 to Angiotensin 2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Angiotensin 2 activates AT1 receptors which cause what?

A
  • Contraction of vascular smooth muscle
  • Secretion of aldosterone
  • Increased reabsorption of sodium
  • norepinephrine release
  • Stimulation of cell growth in arteries and heart
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are some examples of ACE inhibitors?

A

Ramipril, perindopril, captopril, lisinopril

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Where is ACE mainly expressed and what are ACE inhibitors mechanism of action?

A

In the lungs.

  1. Binds to the zinc atom in the active site of ACE preventing conversion of Angiotensin 1 to Angiotensin 2.
  2. Reduction of circulating Angiotensin 2 lowers blood pressure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What drug interactions are there with ACE inhibitors?

A

Diuretics/CCBs -> effect increased (can be used in resistant hypertension)
Potassium sparing diuretics -> hyperkalaemia
Lithium -> Lithium toxicity
NSAIDSs -> impedes antihypertensive effects

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the adverse effects of ACE inhibitors?

A
  • Dry cough (buildup of bradykinin usually cleaved by ACE) - major compliance issue
  • Can cause foetal injury and death - MUST NOT BE USED IN PREGNANCY
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are examples of angiotensin receptor blockers (ARBs), what is their mechanism of action and what is their advantage over ACE inhibitors?

A

Candesartan, Irbesartan, losartan.

Selectively block Antgiotensin AT1 receptors, reducing Angiotensin 2 mediated effects.

Do not cause dry cough.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the main contraindication of ARBs?

A

Pregnancy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the name of the only direct renin inhibitor and how does it work?

A

Aliskiren, binds to active site of renin, prevents cleavage of angiotensinogen to angiotensin 1
(Can be used as ARB adjunct)

17
Q

What are the function of the kidneys?

A

Eliminate waste products from the blood while recycling electrolytes and water, and regulating blood pressure.

18
Q

What are examples of Thiazide(-like) diuretics and how do they reduce blood pressure?

A

Hydrochlorothiazide, indapamide.
Reduce BP by increasing sodium and water excretion

19
Q

What are the indications of thiazides and thiazide-like diuretics?

A

Management of CVD
Indapamide also possesses vasodilatory properties (can also be used for HF)

20
Q

What are the side effects of thiazides and thiazide like diuretics?

A
  • Can evoke compensatory renin release
  • potential hypokalaemia
  • can elevated blood glucose, and cholesterol levels
  • Can reduce insulin sensitivity
  • Can potentate the effect of loop diuretics
21
Q

What are examples of loop diuretics, what is their mechanism of action and where do they act on?

A

Furosemide, Bumetanide, Torsemide

Increased excretion of sodium, potassium, chloride, magnesium and calcium ions and water - act on the water-impermeable thick ascending limb (TAL) of the loop of henle

22
Q

Loop diuretics are preferred in which patients?

A

Renal impairment, as thiazides ineffective in CrCLl <3mL/min

23
Q

What are the adverse effects of loop diuretics?

A
  • Electrolyte abnormalities
  • Inc. blood glucose like thiazides
  • Can cause ototoxicity
24
Q

What are the two types of potassium sparing diuretics?

A

Sodium channel blockers (e.g. Amiloride) and Aldosterone receptor antagonists (e.g. Spironolsctone, Eplerone)

25
Q

What are the adverse effects of potsssium-sparing diuretics?

A
  • Hyperkalaemia
  • Aldosterone antagonists -> Gynaecomastia in men (Not Eplerone as is specific)
26
Q

What are examples and the mechanism of action of ADH antagonists?

A

Conivaptan and Tolvaptan.
Significant water loss without high electrolyte loss (antagonism of V2 receptor)

27
Q

What is the adverse effect of ADH antagonists?

A

Hypernatraemia if excessive doses used