PCSK9 and familial hypercholesterolemia: Available experimental data indicated that neointima formation is not strictly dependent on the presence of hypercholesterolemia, and suggested that the influence of increased cholesterol levels on the arterial response to injury in mice might be dependent on several experimental factors, such as the genotype, the type of vessel involved (carotid versus femoral), the age of the animals, dietary scheme, and some local molecular factors, including PCSK9 [7,8,9,10,11].