Antithrombotic potential of olive oil administration in rabbits with elevated cholesterol

Olive oil is the main source of dietary fatty acids in the Mediterranean re gion. The objective of this study was to evaluate the effect of dietary sup plementation with virgin olive oil in an experimental model with rabbits fe d an atherogenic diet (saturated fat 48% of total fat). Four different grou ps of 10 animals each were studied: (1) normolipemic diet (NLD), (2) athero genic diet or saturated fatty acid-enriched diet (SFAED), (3) NLD with 15% olive oil (NLD + OLIV), and (4) SFAED with 15% virgin olive oil (SFAED + OL IV). The animals were fed the experimental diets for 6 weeks, after which w e determined serum lipid profile (total cholesterol, HDL-cholesterol, and t riglycerides), platelet aggregation, platelet thromboxane Bz, aortic prosta cyclin, and platelet and vascular lipid peroxidation. Scanning electron mic roscopic images of the vascular endothelium were studied, as were morphomet ric parameters in the arterial wall and thrombogenicity of the subendotheli um (annular perfusion chamber). Animals fed the SFAED showed platelet hyper activity and increased subendothelial thrombogenicity. Animals fed the SFAE D + OLIV showed, compared with the SFAED group, an improved lipid profile w ith decreased platelet hyperactivity and subendothelial thrombogenicity and less severe morphological lesions of the endothelium and vascular wall. We conclude that supplementation of the SFAED with 15% olive oil reduced vasc ular thrombogenicity and platelet activation in rabbits. Although the perce ntage of olive oil in the diet was higher than the amount in the human diet , these results may be helpful in determining the effect of olive oil in th e human thrombogenic system. (C) 2000 Elsevier Science Ltd. All rights rese rved.