Page 187 - pharma 1 theoretical updated MNU_Neat

Clinical pharmacy 2024/2025 Level 3 Pharm D Pharmacology 1 (PO 502)
Angiotensin II (ANG-II) effects

● ANG-II is a potent vasoconstrictor agent causing an increase in blood
Blood pressure
pressure.
● It stimulates aldosterone synthesis and release (Na+/H2O retention)
Adrenal cortex ● ANG-II acts on the kidney to cause renal vasoconstriction, increase

and kidney proximal tubular sodium reabsorption, and inhibit the release of
renin.
Central nervous ● ANG-II acts on the CNS to stimulate drinking and increase the

system secretion of vasopressin and adrenocorticotropic hormone (ACTH).

Drugs That Block Renin Release

● Propranolol and other β-adrenoceptor blocking drugs, which act by blocking the renal β-
receptors, are involved in the sympathetic control of renin release.
Renin Inhibitors

• Aliskiren was the first nonpeptide renin inhibitor to be approved for the treatment of

hypertension
Angiotensin-Converting Enzyme Inhibitors (ACEIs)

● Orally active ACE inhibitors are directed against the active site of ACE such as captopril

and enalapril.
● ACE inhibitors decrease systemic vascular resistance without increasing heart rate and
promote natriuresis.

● ACE inhibitors block the conversion of ANG-I to ANG-II
● They inhibit the degradation of bradykinin and substance P.
● The action of ACE inhibitors to inhibit bradykinin metabolism contributes significantly

to their hypotensive action.
● Bradykinin also causes the most famous side effect for ACEIs cough
Angiotensin Receptor Blockers

● ANG-II receptor blockers such as losartan and valsartan,

● Lower incidence of cough.

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