Angiotensin receptor blockade with candesartan attenuates atherosclerosis, plaque disruption, and macrophage accumulation within the plaque in a rabbit model

Circulation. 2004 Oct 5;110(14):2060-5. doi: 10.1161/01.CIR.0000143627.55926.4C. Epub 2004 Sep 27.

Abstract

Background: Little is known about whether direct angiotensin receptor blockade can reduce atherosclerosis and plaque disruption. This study evaluated the effect of angiotensin receptor blockade on both the development of atherosclerosis and the disruption of plaque in a modified Constantinides animal model.

Methods and results: Twenty-eight New Zealand White rabbits underwent aortic balloon injury followed by a 1% cholesterol diet for 8 weeks. Thirteen rabbits received candesartan at 0.5 mg x kg(-1) x d(-1) beginning 2 days before aortic balloon injury and continued for the total 8 weeks of the cholesterol diet. The rabbits were then pharmacologically triggered and humanely killed, and their aortas were analyzed. The degree of atherosclerosis was determined by intima-media ratio of the infrarenal portion of the aorta. The frequency of intra-aortic thrombosis, a measure of plaque disruption, and the percentages of macrophage area and collagen-staining area of the plaque were determined. Candesartan-treated rabbits had less atherosclerosis (intima-media infrarenal aorta ratio of 1.18+/-0.08 versus 1.57+/-0.08 [mean+/-SEM] for the placebo group, P<0.001); fewer thrombi (3 of 13 versus 11 of 15; P<0.05); lower percentage area of macrophages to total plaque (18.8+/-2.7% versus 27+/-2.5%, P<0.05); and higher collagen to total plaque area (45+/-3% versus 35+/-2%, P<0.01).

Conclusions: These results demonstrate that angiotensin receptor blockade attenuates the degree of atherosclerosis and reduces both plaque disruption and macrophage accumulation while increasing collagen deposition in the aortas of this animal model.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Angiotensin II Type 1 Receptor Blockers / pharmacology
  • Angiotensin II Type 1 Receptor Blockers / therapeutic use*
  • Animals
  • Aorta / injuries*
  • Aorta / pathology
  • Aortic Diseases / drug therapy*
  • Aortic Diseases / pathology
  • Aortic Diseases / therapy
  • Arteriosclerosis / drug therapy*
  • Arteriosclerosis / pathology
  • Arteriosclerosis / therapy
  • Benzimidazoles / pharmacology
  • Benzimidazoles / therapeutic use*
  • Biphenyl Compounds / pharmacology
  • Biphenyl Compounds / therapeutic use*
  • Catheterization / adverse effects*
  • Cholesterol / blood
  • Cholesterol, Dietary / toxicity
  • Drug Evaluation, Preclinical
  • Endothelium, Vascular / injuries
  • Endothelium, Vascular / pathology
  • Macrophages / drug effects*
  • Rabbits
  • Rupture, Spontaneous
  • Tetrazoles / pharmacology
  • Tetrazoles / therapeutic use*

Substances

  • Angiotensin II Type 1 Receptor Blockers
  • Benzimidazoles
  • Biphenyl Compounds
  • Cholesterol, Dietary
  • Tetrazoles
  • Cholesterol
  • candesartan cilexetil