High production of NO by iNOS can have beneficial microbicidal, antiviral, antiparasitic, and antitumor effects [3, 8, 9], but aberrant iNOS induction may have detrimental consequences and seems to be involved in the pathophysiology of conditions such as tumor development, transplant rejection, and septic shock, in diseases such as asthma, rhinitis, multiple sclerosis, psoriasis, and neurodegenerative diseases [7, 9, 10]. This evidence concerns the gene NOS2 and psoriasis.