The quantification of vitamin D receptors in coronary arteries and their association with atherosclerosis

Objective: The activated vitamin D receptor (VDR) may have an important role in vascular health. The objective of this study was to determine whether there is an association between the expression of VDRs in coronary arteries and the extent of diet-induced atherosclerosis. Methods: Utilizing a cohort of 39 postmenopausal female cynomolgus monkeys with varying stages of atherosclerosis, histologic sections of the left anterior descending artery (LAD) were analyzed for plaque cross-sectional area, plaque thickness, and VDR quantity using immunohistochemical H-score analysis. The quantities of VDRs were analyzed as a continuous variable and were divided at the median intimal H-score into high vs. low groupings. Results: In the LAD, a significant negative correlation was observed between the quantity of VDR and plaque size (both cross-sectional area [p < 0.001] and plaque thickness [p < 0.001]). Monkeys in the low VDR group had a significantly greater cross-sectional plaque area (1.2 mm(2)) and greater plaque thickness (0.3 mm) than those in the high VDR group (0.4 mm(2), p = 0.005; 0.1 mm, p = 0.003, respectively). Conclusions: Lower concentrations of VDRs in a main coronary artery were associated with greater atherosclerotic plaque size in postmenopausal female monkeys. Given that coronary artery atherosclerosis is a major cause of coronary heart disease in postmenopausal women, further research to ascertain the relationship between VDRs and atherosclerosis is warranted. (C) 2012 Elsevier Ireland Ltd. All rights reserved.