Renal I - Inhibitors of RAS Flashcards
Certain ___ syndromes, ____ of the liver, and ___ are associated with excessive body fluid volume and ___.
nephritic; cirrhosis; CHF; edema
Two primary classes of pharmacological agents used to modify abnormal body fluid volume status?
What are these used to treat?
Modifiers of the renin-angiotensin system and diuretics
CHF, hypertension, cirrhosis, and renal disease
ACE Inhibitors:
Primary action? Duration?
Short term effects of reducing body sodium, fluid volume, and BP
What blocks the kidney from forming renin?
What blocks angiotensinogen from being converted to angiotensin I?
Beta adrenergic antagonists
Aliskirin blocks conversion to Angiotensin I
What are 2 functions of ACE inhibitors?
Block the conversion of Angiotensin I to Angiotensin II
Prevent the breakdown of bradykinin
Where do angiotensin receptor inhibitors act?
Block the activation of Angiotensin II on the Adrenal cortex and arterioles
Angiotensin II:
- How does it alter peripheral resistance?
- What action does it have on noradrenergic transmission?
- Direct vasoconstriction
- Increased NE release/decreased NE reuptake, and increases vascular response
Angiotensin II:
Altered peripheral resistance:
- What part of the ANS does it control? Action?
- Acts to release ____ from where?
- What is the ultimate result?
- Increases sympathetic discharge in the CNS
- Catecholamines from the adrenal medulla
- Rapid pressor response
Angiotensin II:
Renal function:
- What is its direct effect on renal function?
- It stimulates release of ____ from the adrenal cortex. This results in increase ___ reabsorption and increased ___ excretion.
- Increase Na+ reabsorption in the proximal tubule
- aldosterone; Na+; K+
Angiotensin II:
Renal function:
- How does it alter renal hemodynamics?
- Ultimate result?
- Direct renal vasoconstriction, enhances NE neurotransmission though increase SNS tone
- Slow pressor response
Angiotensin II:
Nonhemodynamic mediated effects on the heart:
- Use results in increased expression of?
- Use results in increased production of? Synthesis of?
- Proto-oncogenes
- Growth factors; ECM proteins
Angiotensin II:
Hemodynamic mediated effects on the heart:
- Results in increased ___ on the heart.
- What does it do to the vasculature?
- What is the ultimate result?
- afterload
- Increases wall tension
- Use of angiotensin II ultimately causes vascular and cardiac hypertrophpy and remodeling
ACE Inhibitors:
Principle effects:
- What do they inhibit? What happens to levels of plasma AII?
- Other interactions with the renin-angiotensin system?
- Bradykinin stimulates ___ biosynthesis. This helps in the reduction of?
- Inhibit conversion of angiotensin I to angiotensin II; they reduce but do not abolish plasma AII levels
- They do not interact directly with other components
- prostaglandin; blood pressure
ACE Inhibitors:
3 classes? Which are active vs prodrug?
a. sulfhydryl-containing ACE inhibitors - active
b. Dicarboxyl-containing ACE inhibitors - inactive prodrug
c. Phosphorous containing ACE inhibitors - active
Common features of all ACE inhibitors:
- All effectively block?
- All have similar?
- what does this say about current recommendation?
- All ACEI effectively block the conversion of AI to AII
- All ACEI have similar therapeutic indications, adverse-effect profiles, and contraindications
- Thus with the above information, there is NO compelling reason to favor one ACE inhibitor over another
Common features of all ACE inhibitors:
What patients are hyper-responsive to ACE inhibitor induced hypotension? What should be done?
Patients with elevated plasma renin activity are more suceptible to becoming hypotensive; The initial dose should be reduced in these patients (CHF, Na+ depleted patients etc)
Common features of all ACE inhibitors:
ACE inhibitors are eliminated by the kidney - What does this mean for someone with renal failure? How should medication be altered?
What are the two exceptions to this? Why?
Someone with renal failure will have decreased clearance and thus the medication dosage should be lowered
Fosinopril and Spirapril are exceptions to this because they are eliminated by the liver and kidney
What is the main sulfhydryl-containing ACE inhibitor?
What is the main phosphorous-containing ACE inhibitor?
Captopril
Fosinopril
What is the main dicarboxyl-containing ACE inhibitor?
Name 7 others?
Enalapril
Lisinopril, benazepril, quinapril, moexipril, ramipril, trandolapril, perindopril
What are the therapeutic uses of ACE inhibitors?
Hypertension, left ventricular systolic dysfunction, CHF, Acute MI, patients at high risk for CV events, and chronic renal failure
Therapeutic uses of ACE inhibitors:
Hypertension:
- What are the principle beneficial effects to the CV system?
- What type of hypertension does this not effect? Why?
- DECREASED: TPR, MAP, DBP and SBP
- Ace inhibitors do not reduce the hypertension in primary aldosteronism because this occurs downstream from the ACE effects