Topic 10 - Drugs that affect the Cardiovascular System Flashcards
1
Q
Explain why diuretics, ACE inhibitors and angiotensin II receptor antagonists are indicated for hypertension and
heart failure by referring to their pharmacodynamics and pharmacological effects.
A
Competitively inhibits ACE from converting angiotensin I to angiotensin II. Lowered levels of angiotensin II results in:
- Decreased vasoconstriction → decreased TPR → decreased MAP
- Decreased aldosterone secretion → decreased sodium reabsorption → decreased blood volume → decreased cardiac output → decreased MAP
- Decreased ADH secretion → decreased water reabsorption → decreased blood volume → decreased CO → decreased MAP
- Decreased sympathetic activity → decreased TPR & CO → decreased MAP
Inhibition of ACE results in a ↓ in vascular tone, and direct lowering of BP
