Ahmet ERGÜN, E.Oğuzhan OĞUZ, M. Cengiz GÜVEN, Belgin CAN, Fuat ERTEN, Yüksel SARAN

Nikotinin ince yapı düzeyinde sıçanlarda beyin frontal korteksine etkisi

Amaç: Nikotin gelişmekte olan ülkelerde sigara içimiyle yaygın bir şekilde aktif ya da pasif olarak maruz kalınan multisistemik etkisi olan bir nöroteratojen ve nörotoksik bir ajandır. Daha önceleri nikotinin sinir dokusu ve çeşitli dokulara etkileri araştırılmıştır. Çalışmamızda nikotin maruziyetinin sıçan beyni frontal korteksi ince yapısı üzerine etkisinin araştırılması amaçlandı. Materyal ve Metod:On erişkin Wistar Albino sıçana 10 gün boyunca günde 0.4mg/kg nikotin damar içi enjekte edildi. Benzer yaş ve kiloda on kontrol sıçana aynı sürede serum fizyolojik verildi. Elde edilen dokular transmisyon elektron mikroskobu için hazırlanarak incelendi. Bulgular: Nikotin verilen sıçanlarda kan damarlarının bazal membranlarında yer yer kalınlaşma ve incelme, endotel hücrelerinde dejenerasyonlar, nikotine maruz kalan sinir hücrelerinde lipit damlacıklarının arttığı ve bol miktarda nörofilaman ve nekroz odakları görüldü. Sonuç: İncelememizde beynin frontal bölgesinin damar endotelinde ve sinir hücrelerinde nikotinin zararlı etkilerini gösteren değişiklikler söz konusuydu.

Anahtar Kelimeler:

Mikroskopi, elektron, geçirim, Nikotin, Sıçan, Wistar, Nörotoksisite sendromları, Modeller, hayvan, ince yapı, Beyin, Sıçanlar

The ultrastructural effect of nicotine on rat frontal cortex

Aim: Nicotine which is generally exposed by cigarette smoking is a neuroteratogen and neurotoxic agent. It has multisystemic effects. The effects of nicotine in different systems have been reported previously. In our study, we aimed to investigate the effect of nicotine on adult rat brain frontal cortex. Materials and Methods: Ten rats were injected intravenously with nicotine at a dose of 0,4 mg/kg body weight daily for 10 days; ten control rats matched for age and weight were injected with saline only for the same duration. The tissues were then harvested and examined by transmission electron microscopy. Results: Rats given nicotine showed thickenning and thinning of the basillar membrane of blood vessels and endothelial cellular changes and degeneration. Increased number of lipid droplets and more abundant filaments were seen in nicotine exposed neurons. Conclusion: There were alterations in rats exposed to nicotine that could be attributed to the detrimental effects of nicotine upon vascular endotelium and neural structures of the frontal cortex of the rat brains.

Keywords:

Microscopy, Electron, Transmission, Nicotine, Rats, Wistar, Neurotoxicity Syndromes, Models, Animal, ultrastructure, Brain, Rats,

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