Pharmacology - Chapter 43 - Drugs Acting on the Renin-Angiotensin System Flashcards
What do these drugs (that act on this system) do? (3)
Regulation blood pressure, regulate blood volume, and regulation electrolyte balance.
What are the 3 types of angiotensin?
1 - Precursor of 2 - has little biological activity.
2 - very high biological activity.
3 - degradation of 2 produces 3 - has moderate activity.
Angiotensin 1 - a decline in blood pressure, a reduction in the blood volume, a decline in sodium content, a decline in renal pressure triggers the production of ___.
Renin.
Renin - produced by _____ - catalyzes ____ from _____ (a serum globuline in the liver.)
Renin - produced by juxtaglomerular cells of the kidney.
Catalyzes angiontensin 1 from angiotensinogen (a serum globuline in the liver.)
Angiotensin Converting Enzyme (ACE, also known as ___ 2.)
Kinase 2.
What does ACE do?
Catalyzes the conversion of Angiotensin 1 (inactive) to Angiotensin 2(highly active!)
Where is ACE located?
On the surface of all blood vessels (especially in the lungs!)
Action of Angiotensin 2 -
mediates all of the effects of the RAS - it acts directly on vascular smooth muscle to cause contraction, and acts indirectly on smooth muscle constriction…..also promotes synthesis and release of aldosterone.
What are the 2 drugs that act on the Renin-Angiotensin system?
Angiotensin converting enzyme (ACE) inhibitors and Angiotensin 2 receptor blockers (ARB’s)
ARB’s are only approved for ___.
Hypertension.
PRIL - ending means an….
ACE inhibitor.
ACE - treatment for….
hypertension and heart failure.
What is the 1st ace inhibitor used worldwide?
Captopril!
What does Captopril do?
Prevents formation of Angiotensin 2 - results in vasodilation.
Captopril is taken ____ and absorption is ___ % but is reduced greatly by ____ (take 1 hour prior to meals.)
Orally - 70 % - food.
