Animal models have also shown a reduction in aortic atherosclerosis with a simultaneous reduction in IL-6 and TNF-α expression and up-regulation of iNOS expression, and that inhibition of iNOS exacerbates atherosclerosis, reduces cortical perfusion and enhances ischemic neuronal damage and impairs Ach-dependent muscle relaxation of the smooth vessels [34]. This evidence concerns the gene NOS2 and aortic atherosclerosis.