Amaç: Çalışmamızda, pinealektomili ve pinealektomi sonrası melatonin uygulanan sıçanlaraait prefrontal korteks doku örneklerinin biyokimyasal düzeyde incelenmesi amaçlandı.Gereç ve Yöntem: 21 adet Wistar-Albino cinsi erkek sıçanlar üç eşit gruba ayrıldı. Grup I’dekisıçanlar kontrol (sham-pinealektomi) olarak kullanıldı. Grup II’ye ait hayvanlara cerrahi olarakpinealektomi yapıldı. Grup III’deki sıçanlara ise pinealektomi sonrası günlük olarak, üç ayboyunca, melatonin hormonu (1 mg/kg/) intraperitoneal yoldan enjekte edildi. Deney süresisonunda bütün sıçanlar dekapite edilerek öldürüldü ve prefrontal korteksleri çıkartıldı. Prefrontalkorteks doku örneklerinde süperoksit dismutaz (SOD), glutatyon peroksidaz (GSH-Px) enzimaktiviteleri ile malondialdehit (MDA) seviyeleri biyokimyasal olarak belirlendi.Bulgular: Pinealektomili sıçanlarda, prefrontal korteks SOD ve GSH-Px enzim değerlerininkontrol grubuna göre anlamlı bir şekilde azaldığı, MDA düzeylerinin ise yine istatistiksel olarakanlamlı bir şekilde arttığı tespit edildi. Pinealektomi sonrası melatonin enjekte edilen sıçanlardaise, doku SOD ve GSH-Px enzim aktivitelerinin yükseldiği, MDA seviyelerinin de azaldığıtespit edildi.Sonuç: Bu çalışma sonucunda, sıçanlarda pinealektomiye bağlı olarak prefrontal korteks’temeydana gelen oksidatif doku hasarının melatonin enjeksiyonu ile önlendiği tespit edildi
Aim: An attempt was made to investigate the tissue samples of prefrontal cortex frompinealectomized rats and melatonin applied rats following pinealectomy in biochemical basis.Materials and Methods: Twenty-one, male Wistar rats were divided equally into three groups.Rats in Group I were used as control (sham-pinealectomy). Rats in Group II werepinealectomized. Rats in Group III were injected daily with melatonin (1 mg/kg/)intraperitoneally for 3 months following pinealectomy. At the end of the experimental period,all rats were killed by decapitation and the prefrontal cortexes of rats were removed. Superoxidedismutase (SOD), glutathione peroxidase (GSH-Px) enzyme activities and malondialdehyde(MDA) levels were determined at biochemical levels in the prefrontal cortex specimens.Results: The levels of SOD and GSH-Px in the prefrontal cortex tissue were significantlydecreased and MDA levels were significantly increased in pinealectomized rats compared withthose of the controls. However, increased activities of SOD and GSH-Px enzymes and decreasedlevels of MDA were detected in the rats administered melatonin following pinealectomy.Conclusion: As a result of this study, pinealectomy-induced oxidative damage in the prefrontalcortex tissue in rats were prevented by administration of melatonin hormone
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