[The effect of temocapril, an angiotensin-converting enzyme inhibitor with preferential biliary excretion, on...

Tempocapril is a novel angiotensin-converting enzyme (ACE) inhibitor which is preferentially eliminated via the biliary tract. To examine whether it has a protective effect in diabetic nephropathy like conventional ACE inhibitors which are eliminated via the kidney, a study was performed in streptozotocin-induced diabetic rats for 8 months. Male Wistar rats were divided into 4 groups (control rats, diabetic rats treated with temocapril at the doses of 5 mg/l or 15 mg/l of drinking water, and untreated diabetic rats). There was no significant difference in the blood glucose levels of the 3 diabetic groups. Administration of temocapril at both doses of 5 mg/l and 15 mg/l significantly reduced the blood pressure as well as the urinary excretion of albumin and N-acetyl-beta-D-glucosaminidase. However, significant suppression of glomerular basement membrane hypertrophy was only induced by treatment with temocapril at the dose of 15 mg/l. Elevated glomerular filtration rate and filtration fraction in diabetic rats were decreased by tempocapril at the dose of 15 mg/l, but not significantly. These results indicate that tempocapril has a protective effect on diabetic nephropathy like conventional ACE inhibitors.