Prinivil, Zestril Lisinopril
Mechanism of action
They inhibit the converting enzyme which is responsible for the conversion of angiotensin 1 into angiotensin 2. Angiotensin 1 is a decapeptide that is formed from a plasma protien alpha globulin (angiotensinogen)by the action of renin. Renin is formed in the kidney.Angiotensin 1 is converted into angiotensin 2 by the converting enzyme in the blood vessels of the lungs that is an octapeptide. Angiotensin 2 is a powerful vasoconstrictor and it causes increased production of aldosterone from adrenal cortex.Aldosterone then causes the increase reabsoprtion of salt and water from the renal tubules.Angiotensin 2 is converted into angiotensin 3 that also increase the secretion of aldosterone from the adrenal cortex. Thus both angio 2 and angio 3 are responsible for increase in BP. Also ACE inhibitors prevent the destruction of bradykinin by angitensin converting enzyme that further decrease the blood pressure by causing dilation of peripheral blood vessel. Bradykinins is also a potent vasodilator but it partialy acts by causing the release of nitric oxide and prostacylin. Bradykinin is also responsible for causing cough and angioedema in some persons using ACE inhibitors.
ACE inhibitors are used for:
- Controlling high blood pressure
- Treating left ventricular dysfunction and heart failure
- Preventing and treating kidney disease (nephropathy) in people with hypertension or diabetes
- Preventing strokes
Side effects may include dry cough,low blood pressure (hypotension),high potassium levels (hyperkalemia), dizziness,angioedema,reduced kidney function.
Do not use this medicine if you are pregnant, breastfeeding, or planning to get pregnant. If you need to use this medicine, talk to your doctor about how you can prevent pregnancy.