Copper deficient rats exhibit no alterations in plasma or brain NO metabolites, 3‐nitrotyrosine peptide abundance, or NOS mRNA expression

Abstract

Others have reported that copper deficient (Cu−) rodents have alterations in nitric oxide (NO) biology including: higher nitric oxide synthase (NOS) activity and expression, and higher 3‐nitrotyrosine abundance (a marker of peroxynitrite production predicted to be higher because of higher NO and superoxide). Altered NO could impact brain development and metabolism. Holtzman rat dams were fed a Cu− diet and given either Cu supplemented (Cu+) or deionized water starting on gestation day 7. Cu− dams at weaning and their male pups at P26 had near zero plasma ceruloplasmin activity. Compared to Cu+ P26 male rats Cu− rats had heart/body weight values more than twice as high. However, plasma levels of NO metabolites (nitrite and nitrate) were not altered by Cu deficiency in dams or pups. Mean values in all groups were approximately 60 μM. Cerebellar extracts of P24 Cu− and Cu+ rats contained equivalent NO metabolite levels; furthermore, a 30kD 3‐nitrotyrosine containing peptide was detected in equal amounts in P24 Cu− and Cu+ cerebellar extracts. However, levels of CCS were markedly higher and CCO subunit IV nearly absent in Cu− lanes confirming severe Cu deficiency. Abundance of brain nNOS and eNOS mRNA, detected by real time qPCR, was not different between Cu− and Cu+ rat pups. We conclude perturbation in NO biology is unlikely to impact the altered development and metabolism of Cu− rat brain.Supported in part by NIH HD‐39708.