title: Effects of hyperthyroidism induced by L-thyroxin administration on lipid peroxidation in various rat tissues.
abstract: Thyroid dysfunctions are associated with many pathological signs in the body. One of these is lipid peroxidation that develops due to over- or under-secretion of thyroid hormones. The present study was conducted to determine lipid peroxidation that develops in different tissues including the brain, liver and heart of rats in experimental hyperthyroidism induced by L-thyroxin. The study was carried out on 30 male Sprague-Dawley rats. They were divided into three groups as control, sham hyperthyroidism and hyperthyroidism. Malondialdehyde (MDA) and glutathione (GSH) levels in rat tissues were determined at the end of a 3-weeks period of L-thyroxin administration. It was observed that MDA levels in the hyperthyroidism group were significantly higher in the cerebral cortex, liver and ventriculer tissue of heart (p < 0.001) than in the control and in sham hyperthyroidism groups. GSH levels were higher in the hyperthyroidism group than in control and sham hyperthyroidism groups in all tissues (p < 0.001). Results demonstrate that hyperthyroidism induced by L-thyroxin activates both oxidant and antioxidant systems in cerebral, hepatic and cardiac tissues. However, the increase in antioxidant activity cannot adequately prevent oxidative damage.
authors.affiliation: Department of Physiology, Meram Medical School, Selcuk University, 42080-Konya, Turkey. rasimmogulkoc@yahoo.com
authors.forename: R
authors.initials: R
authors.lastname: Mogulkoc
authors.forename: A Kasim
authors.initials: AK
authors.lastname: Baltaci
authors.forename: Esma
authors.initials: E
authors.lastname: Oztekin
authors.forename: A
authors.initials: A
authors.lastname: Sivrikaya
authors.forename: Leyla
authors.initials: L
authors.lastname: Aydin
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D001923:Brain Chemistry; D005978:Glutathione / Q000737:chemistry / Q000378:metabolism; D006980:Hyperthyroidism / Q000139:chemically induced / Q000378:metabolism; D015227:Lipid Peroxidation; D008099:Liver / Q000737:chemistry; D008297:Male; D008315:Malondialdehyde / Q000737:chemistry / Q000378:metabolism; D009206:Myocardium / Q000737:chemistry; D016877:Oxidants / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D013974:Thyroxine / Q000008:administration & dosage / Q000633:toxicity*; D014020:Tissue Extracts / Q000737:chemistry
chemical_list: D000975:Antioxidants; D016877:Oxidants; D014020:Tissue Extracts; D008315:Malondialdehyde; D005978:Glutathione; D013974:Thyroxine