SIÇAN PREFRONTAL KORTEKSİNDE FORMALDEHİT MARUZİYETİYLE OLUŞAN OKSİDATİF HASARA KARŞI MELATONİN HORMONUNUN KORUYUCU ETKİSİ

Yıl 2004, Cilt: 13 Sayı: 2, 1 - 7, 01.09.2004

İlter Kuş İsmail Zararsız H.ramazan Yılmaz Aslı Özdem Türkoğlu Hıdır Pekmez Mustafa Sarsılmaz

Öz

Bu çalışmada, formaldehitin prefrontal korteks üzerine olan nörotoksik etkileri ve bu toksik etkilere karşı melatonin hormonunun koruyucu etkisi biyokimyasal düzeyde araştırıldı. Bu amaçla, 21 adet Wistar-Albino cinsi erkek sıçan üç gruba ayrıldı. Grup I’deki sıçanlar kontrol olarak kullanıldı. Grup II’deki sıçanlara gün aşırı % 10’luk formaldehit intraperitoneal olarak enjekte edildi. Grup III’deki sıçanlara ise, formaldehit enjeksiyonu ile birlikte günlük olarak 25 mg/kg dozunda melatonin uygulandı. Ondört günlük deney süresi sonunda bütün sıçanlar dekapitasyon yöntemi ile öldürüldü. Daha sonra sıçanların beyinleri çıkartılarak, prefrontal korteks örneklerinde süperoksit dismutaz (SOD), glutatyon peroksidaz (GSH-Px) ve malondialdehit (MDA) enzim aktiviteleri spektrofotometrik olarak belirlendi. Formaldehit uygulanan sıçanlarda SOD ve GSH-Px değerlerinin kontrol grubuna göre anlamlı bir şekilde azaldığı, MDA düzeylerinin ise yine istatistiksel olarak anlamlı bir şekilde arttığı tespit edildi. Formaldehit maruziyeti ile birlikte melatonin enjekte edilen sıçanlarda, SOD ve GSH-Px enzim aktivitelerinde bir artış olurken, MDA değerlerinde istatistiksel olarak anlamlı bir düşüş olduğu görüldü. Sıçanlarda, formaldehit maruziyeti sonucu prefrontal kortekste oksidatif hasarın oluştuğu ve bu hasarın melatonin uygulaması ile önlendiği tespit edildi

Anahtar Kelimeler

Formaldehit, melatonin, süperoksit dismutaz, glutatyon peroksidaz, malondialdehit

The Protective Effects of Melatonin Hormone Against Exposure of Formaldehyde-Induced Oxidative Damage in Prefrontal Cortex of Rats

Öz

In this study, neurotoxic effects of formaldehyde on prefrontal cortex and protective effects of melatonin hormone against these toxic effects were investigated at biochemical level. For this purpose, 21 adult male Wistar rats were divided into three groups. Rats in group I were used as control. Rats in group II were injected every other day with 10 % formaldehyde. Rats in group III were daily administered melatonin with (25 mg/kg) injection of formaldehyde. At the end of fourteen-days experimental period, all rats were killed by decapitation. Then the brains of rats were removed. The activites of superoxide dismutase (SOD), glutathione peroxidase (GSHPx) and malondialdehyde (MDA) were determined in the prefrontal cortex specimens by using spectrophotometric methods. The levels of SOD and GSH-Px were significantly decreased, and MDA levels were significantly increased in rats treated with formaldehyde compared to control. It was seen that increase of SOD and GSH-Px enzyme activities, and decrease of MDA levels in rats administered melatonin with exposure of formaldehyde. It was determined that exposure of formaldehyde caused oxidative damage in prefrontal cortex of rats and this damage was prevented by administration of melatonin

Anahtar Kelimeler

Formaldehyde, melatonin, superoxide dismutase, glutathione peroxidase, malondialdehyde

Kaynakça

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