Candesartan and enalapril similarly reduced the media-to-lumen ratio of small arteries, but candesartan uniquely reduced vascular collagen content in hypertensive patients with NIDDM.
Does candesartan compared to enalapril improve subcutaneous small artery structure in patients with mild hypertension and NIDDM?
Both candesartan and enalapril improve small resistance artery structure in hypertensive diabetic patients, but candesartan may uniquely reduce vascular collagen content.
Structural alterations of subcutaneous small resistance arteries are associated with a worse clinical prognosis in hypertension and noninsulin-dependent diabetes mellitus (NIDDM). However, no data are presently available about the effects of antihypertensive therapy on vascular structure in hypertensive patients with NIDDM. Therefore, we have investigated the effect of an angiotensin-converting enzyme inhibitor, enalapril, and a highly selective angiotensin receptor blocker, candesartan cilexetil, on indices of subcutaneous small resistance artery structure in 15 patients with mild hypertension and NIDDM. Eight patients were treated with candesartan (8 to 16 mg per day) and 7 with enalapril (10 to 20 mg per day) for 1 year. Each patient underwent a biopsy of the subcutaneous fat from the gluteal region at baseline and after 1 year of treatment. Small arteries were dissected and mounted on a micromyograph and the media-to-internal lumen ratio was evaluated; moreover, endothelium-dependent vasodilation to acetylcholine was assessed. A similar blood pressure-lowering effect and a similar reduction of the media-to-lumen ratio of small arteries was observed with the 2 drugs. Vascular collagen content was reduced and metalloproteinase-9 was increased by candesartan, but not by enalapril. Changes of circulating indices of collagen turnover and circulating matrix metalloproteinase paralleled those of vascular collagen. The 2 drugs equally improved endothelial function. In conclusion, antihypertensive treatment with drugs that inhibit the renin-angiotensin-aldosterone system activity is able to correct, at least in part, alterations in small resistance artery structure in hypertensive patients with NIDDM. Candesartan may be more effective than enalapril in reducing collagen content in the vasculature.
Rizzoni et al. (Tue,) conducted a other in mild hypertension and noninsulin-dependent diabetes mellitus (n=15). candesartan cilexetil vs. enalapril was evaluated on media-to-internal lumen ratio of subcutaneous small resistance arteries. Candesartan and enalapril similarly reduced the media-to-lumen ratio of small arteries, but candesartan uniquely reduced vascular collagen content in hypertensive patients with NIDDM.