title: Thyroid hormones affect the level and activity of nitric oxide synthase in rat cerebral cortex during postnatal development.
abstract: The effects of thyroid hormones (TH) on the enzyme level and activity of neuronal nitric oxide synthase (nNOS) were studied in the rat cerebral cortex during postnatal life. As revealed by arginine/citrulline conversion assay and Western blot analysis of the homogenate of the parietal cortex T4 significantly increased nNOS activity and nNOS protein level to 153 +/- 25% and to 178 +/- 20%, respectively. In contrast, 6-n-propyl-2-thyouracil (PTU) decreased nNOS activity and nNOS level to 45 +/- 10% and to 19 +/- 4%, respectively. The number of nNOS-immunoreactive neurons did not change after either T4 or PTU treatment, however, following T4 administration the percentage of intensively immunoreactive neurons increased to 85 +/- 3% compared to control (65 +/- 6%), whereas it decreased to 49 +/- 2% after PTU treatment. Our findings indicate that abnormal TH levels differentially regulate the activity and the level of nNOS and suggest a cross-talk between the TH and NO signaling pathway in the developing cerebral cortex of rats.
authors.affiliation: Department of Experimental Zoology, Balaton Limnological Research Institute, Hungarian Academy of Sciences, Klebelsberg Kuno u. 3, Tihany 8237, Hungary. serfozo@tres.blki.hu
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Serfozo
authors.forename: Péter B
authors.initials: PB
authors.lastname: Kiss
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Kukor
authors.forename: Beáta
authors.initials: B
authors.lastname: Lontay
authors.forename: Károly
authors.initials: K
authors.lastname: Palatka
authors.forename: Vince
authors.initials: V
authors.lastname: Varga
authors.forename: Ferenc
authors.initials: F
authors.lastname: Erdodi
authors.forename: Károly
authors.initials: K
authors.lastname: Elekes
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D013956:Antithyroid Agents / Q000494:pharmacology; D015153:Blotting, Western; D002540:Cerebral Cortex / Q000187:drug effects / Q000201:enzymology* / Q000254:growth & development*; D007150:Immunohistochemistry; D052248:Nitric Oxide Synthase Type I / Q000096:biosynthesis*; D011441:Propylthiouracil / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D013963:Thyroid Hormones / Q000494:pharmacology*; D013974:Thyroxine / Q000494:pharmacology
chemical_list: D013956:Antithyroid Agents; D013963:Thyroid Hormones; D011441:Propylthiouracil; D052248:Nitric Oxide Synthase Type I; D013974:Thyroxine