title: Postnatal changes in the nitric oxide system of the rat cerebral cortex after hypoxia during delivery.
abstract: The impact of hypoxia in utero during delivery was correlated with the immunocytochemistry, expression and activity of the neuronal (nNOS) and inducible (iNOS) isoforms of the nitric oxide synthase enzyme as well as with the reactivity and expression of nitrotyrosine as a marker of protein nitration during early postnatal development of the cortex. The expression of nNOS in both normal and hypoxic animals increased during the first few postnatal days, reaching a peak at day P5, but a higher expression was consistently found in hypoxic brain. This expression decreased progressively from P7 to P20, but was more prominent in the hypoxic group. Immunoreactivity for iNOS was also higher in the cortex of the hypoxic rats and was more evident between days P0 and P5, decreasing dramatically between P10 and P20 in both groups of rats. Two nitrated proteins of 52 and 38 kDa, were also identified. Nitration of the 52-kDa protein was more intense in the hypoxic animals than in the controls, increasing from P0 to P7 and then decreasing progressively to P20. The 38-kDa nitrated protein was seen only from P10 to P20, and its expression was more intense in control than in the hypoxic group. These results suggest that the NO system may be involved in neuronal maturation and cortical plasticity over postnatal development. Overproduction of NO in the brain of hypoxic animals may constitute an effort to re-establish normal blood flow and may also trigger a cascade of free-radical reactions, leading to modifications in the cortical plasticity.
authors.affiliation: Neuroanatomy and Cell Biology Department, Instituto Cajal (CSIC), Avenida del Doctor Arce 37, 28002, Madrid, Spain.
authors.forename: Ana Patricia
authors.initials: AP
authors.lastname: Fernández
authors.forename: David
authors.initials: D
authors.lastname: Alonso
authors.forename: Ignacio
authors.initials: I
authors.lastname: Lisazoaín
authors.forename: Julia
authors.initials: J
authors.lastname: Serrano
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Leza
authors.forename: María Luisa
authors.initials: ML
authors.lastname: Bentura
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: López
authors.forename: Juan
authors.initials: J
authors.lastname: Manuel Encinas
authors.forename: Paula
authors.initials: P
authors.lastname: Fernández-Vizarra
authors.forename: Susana
authors.initials: S
authors.lastname: Castro-Blanco
authors.forename: Alfredo
authors.initials: A
authors.lastname: Martínez
authors.forename: Ricardo
authors.initials: R
authors.lastname: Martinez-Murillo
authors.forename: Pedro
authors.initials: P
authors.lastname: Lorenzo
authors.forename: Juan Angel
authors.initials: JA
authors.lastname: Pedrosa
authors.forename: María Angeles
authors.initials: MA
authors.lastname: Peinado
authors.forename: José
authors.initials: J
authors.lastname: Rodrigo
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001238:Asphyxia Neonatorum / Q000378:metabolism* / Q000503:physiopathology; D002454:Cell Differentiation / Q000502:physiology; D002540:Cerebral Cortex / Q000201:enzymology* / Q000254:growth & development* / Q000503:physiopathology; D002560:Cerebrovascular Circulation / Q000502:physiology; D004195:Disease Models, Animal; D005260:Female; D005609:Free Radicals / Q000378:metabolism; D006801:Humans; D002534:Hypoxia, Brain / Q000201:enzymology* / Q000503:physiopathology; D007150:Immunohistochemistry; D007231:Infant, Newborn; D009473:Neuronal Plasticity / Q000502:physiology; D009474:Neurons / Q000201:enzymology*; D009566:Nitrates / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism*; D019001:Nitric Oxide Synthase / Q000378:metabolism*; D011247:Pregnancy; D051381:Rats; D017208:Rats, Wistar; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000378:metabolism; D015854:Up-Regulation / Q000502:physiology
chemical_list: D005609:Free Radicals; D009566:Nitrates; D009569:Nitric Oxide; C002744:3-nitrotyrosine; D014443:Tyrosine; D019001:Nitric Oxide Synthase