ACE inhibitors are contraindicated in bilateral renal aery stenosis, because -

Ans. is 'a' i.e., Angiotensin II has direct effect on GFR o Patients with renal aery stenosis are dependent on efferent aeriolar vasoconstiction for maintenance of glomerular filtration pressure. Angiotensin II is responsible for vasoconstriction of efferent aeriole. o ACE inhibitors prevent the generation of Angiotensin II. This causes dilatation of efferent aerioles and fall in glomerular filtration pressure. This can ppt renal failure. o Therefore ACE inhibition are C/I in patients with bilateral renal aery stenosis.