Is Ramipril the pril for diabetes and kidney disease?
Ramipril is safe and effective in the treatment of hypertension and heart failure, but this is not reviewed here. Ramipril is a lipophilic angiotensin-converting enzyme inhibitor suitable for once-daily administration. In addition to decreasing angiotensin II and increasing bradykinin levels, ramipril increases the levels of vasodilatory renal medullary neutral lipids and inhibits platelet-derived growth factor-induced proliferation of glomerulus cells. Ramipril also decreases transforming growth factor-beta in the kidney. Changes in kidney structure and proteinuria are characteristics of the streptozotocin (STZ) rat model of diabetes, and these are prevented by ramipril. In STZ diabetes, doses of ramipril that have no effect on blood pressure reverse vascular hypertrophy. In animal models of kidney failure (subtotal nephrectomy, stroke-prone spontaneously hypertensive rats), ramipril is renoprotective and some of this renoprotective effect is independent of blood pressure lowering. In humans, clinical doses of ramipril probably do not modify glucose metabolism but do reduce the levels of LDL- and HDL-cholesterol. In clinical trials of renal effects, ramipril has been shown to increase cortical nephron flow in hypertension and to reduce proteinuria in patients with and without diabetes and/or hypertension. Some of the smaller clinical trials showed beneficial effects on kidney function with low doses of ramipril that do not lower blood pressure. A large clinical trial in nondiabetic proteinuria, the Ramipril Efficacy in Nephropathy (REIN) trial, has shown that ramipril 1.25 mg/day, which does not lower blood pressure, arrested the decline in glomerular filtration rate and prolonged the time to end-stage renal failure. In diabetic patients who have had a previous cardiovascular event or having one other cardiovascular risk factor, the MICRO-HOPE clinical trial showed that ramipril lowers the combined risk of myocardial infarction, stroke and cardiovascular death by 25%. In conclusion, ramipril has proven beneficial effects in kidney disease alone or in association with diabetes and in diabetes without kidney disease, and is the pril for diabetes and kidney disease. (c) 2001 Prous Science. All rights reserved.
Doggrell
Sheila A.
SA
Doggrell Biomedical Communications, Lynfield, Auckland, New Zealand. s-doggrell@yahoo.com