However, in addition to the fact that non-MPO peroxidases could account for the formation of apocynin dimers and trimers in vascular tissue [64], in the present study culture cells are not being evaluated, but a complete arterial segment that could easily contain MPO activity, mainly in hypercholesterolemic animals since hypercholesterolemia facilitates MPO activity increase in vascular tissues [65, 66]. This evidence concerns the gene MPO and familial hypercholesterolemia.