NOS1 and Parkinson disease: Removal of one or both of O2− and NO/ONOO can prevent the deleterious effects of PD model toxins, as reported in transgenic mice deficient in iNOS, nNOS, NADPH oxidase or with overexpression of Mn/SOD conferring resistance to the toxicological effects of MPTP or intrastriatal injection of 6-OHDA [238–243].