Figure 3. Testicular (A; n = 20 for basal wild-type [WT] and n = 21 for stressed; n = 15 for basal neuronal nitric oxide synthase–deficient [KO] and n = 13 for stressed) and adrenal (B; n = 5 for basal WT and n = 4 for stressed; n = 3 for basal KO and n = 3 for stressed), nitrite and nitrate (NOx) levels were measured as described in "Materials and Methods." Data are presented as means ± SEM of NOx in nmol per g tissue. C indicates unstressed control mice; IMO, stressed mice.