What is the effect of ACE inhibitors or ARBs on diabetic nephropathy?

• A. They Reduce Intraglomerular Pressure, Decrease Proteinuria, and Slow Progression of Kidney Disease
• B. They Increase Intraglomerular Pressure
• C. They Have No Effect on Proteinuria
• D. They Worsen Progression

Answer: (A)

The main idea is that diabetic nephropathy is driven by high pressure inside the glomeruli (intraglomerular pressure) that pushes albumin into the urine and accelerates kidney damage. ACE inhibitors and ARBs counter this by blocking the effects of angiotensin II, which normally constricts the efferent arteriole. With these drugs, the efferent arteriole dilates, lowering intraglomerular pressure. That drop in pressure reduces protein leakage (proteinuria) and slows the decline in kidney function, slowing progression of the disease. They can also lower systemic blood pressure, which helps, but the crucial renal effect is the reduction of intraglomerular pressure and proteinuria.