RESUMO
OBJECTIVES: Atherosclerosis is almost absent in intramyocardial coronary arteries, while epicardial coronary arteries may show extensive occlusive disease. Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) expression has been implicated in atherogenesis. We aimed to investigate differences in arterial wall LOX-1 expression between human epicardial and intramyocardial coronary arteries. METHODS: Epicardial and intramyocardial total artery wall specimens were obtained from 13 male patients (aged 61.9 ± 10.3 years) undergoing coronary artery bypass graft surgery due to 3-vessel coronary artery disease. LOX-1 expression was examined by reverse transcription-polymerase chain reaction. RESULTS: LOX-1 expression was significantly higher in the arterial wall of epicardial coronary arteries compared to intramyocardial coronary arteries. The LOX-1/GAPDH ratio was 0.48 ± 0.07 vs. 0.35 ± 0.03 (p < 0.001). CONCLUSIONS: Our findings may partially explain the atheroprotective effect of the intramyocardial course since arterial wall LOX-1 expression was lower in intramyocardial arteries and higher in epicardial coronary arteries.