Reduced progression of atherosclerosis in apolipoprotein E-deficient mice with phenylhydrazine-induced anemia

Epidemiological and experimental studies suggest that circulating erythrocy tes play a role in the incidence of coronary heart disease. We investigated the influence of phenylhydrazine (PHZ)-induced anemia on the formation of atherosclerotic lesions in apo E-deficient mice on regular chow and on a hi gh-fat, high-cholesterol diet during 10 weeks. The repeated doses of PHZ ca used sustained anemia throughout the study, changes in the physical charact eristics of erythrocytes and increased retyculocyte count. The lesions of t he anemic animals were smaller than in the controls and this was even more evident in mice fed with the atherogenic diet. A positive correlation was f ound between circulating red blood cells at the end of the experiment and t he area of aortic lesion. There was also a negative association between the lesion and the retyculocyte count. This reduced progression of atheroscler otic lesions is independent of nutritional status or the lipoprotein choles terol distribution. The results suggest that mechanisms related to the numb er of circulating red blood cells may have a significant influence on the d evelopment of atherosclerosis. (C) 1999 Elsevier Science Ireland Ltd. All r ights reserved.