GENÇ ERKEK SIÇANLARDA E VİTAMİNİ UYGULAMASININ YER BULMA ÖĞRENMESİNE ETKİSİ

Öz

E vitamini alımının bozulmuş öğrenmeyi iyileştirici etkilerinin olduğu birçok çalışmada gösterilmiştir. Ancak sağlıklı deneklerde E vitamini uygulamasının öğrenme üzerindeki etkileri geniş olarak araştırılmamıştır. Özellikle farklı yaş grupları ile yapılan çalışmaların sonuçları arasında çelişkiler bulunmaktadır. Bu çalışmanın amacı, E vitamini uygulamasının sağlıklı genç sıçanlarda yer bulma öğrenmesi ve çalışma belleğine etkisinin Morris su tankında araştırılmasıdır. Bu amaçla, 45 adet, iki aylık, erkek Wistar Albino sıçanla eşit sayıda üç grup oluşturuldu. Kontrol grubuna 0,34 ml/kg/gün serum fizyolojik, çözücü grubuna 0,34 ml/kg/gün zeytinyağı, E vitamini grubuna 40 mg/kg/gün E vitamini 0,26 ml/kg/gün zeytinyağında çözdürülerek 30 gün boyunca günde 1 kez intraperitonel olarak uygulandı. Uygulamaların sonrasında Morris su tankındaki sabit platformun yerini yüzerek bulma yetenekleri, öğrenme ve test fazı ile araştırıldı. Yer bulma öğrenmesinden bir hafta sonra, platformun yeri her gün değiştirilerek çalışma belleği test edildi. Testlerin değerlendirmesinde, platformu bulma süreleri ve platformlu yarı alanda geçirdikleri sürelerin toplam sürenin yüzdesi cinsinden değerleri istatistiksel olarak analiz edildi. Gruplar arasında platformu bulma süreleri ve platformlu yarı alanda geçirdikleri sürelerin toplam sürenin yüzdesi cinsinden değerleri bakımından anlamlı fark bulunmadı. Sonuç olarak çalışmamızda kısa süreli E vitamini uygulamasının, sağlıklı genç erkek sıçanlarda yer bulma öğrenmesi ve çalışma belleği performansını geliştirmediği belirlendi. E vitamini alımının öğrenme üzerine olumlu etkisinin E vitamini alınmaya başlama zamanı ve idame süresiyle ilişkili olabileceği kanısına varıldı

Anahtar Kelimeler

• Öğrenme, bellek, morris su tankı, E vitamini, bilişsel fonksiyon

Effect of Vitamin E Administration on Learning in the Young Male Rats

Öz

Vitamin E supplementation is reported to improve to deteriorated cognitive functions. However, its effects on learning in healthy subjects have not been widely reported. Especially contradictions between age groups related to this condition are encountered. In the present study the influence of vitamin E intake on spatial learning and working memory performances of young rats in the Morris water maze has been investigated. For this purpose, a total of 45 male young Wistar Albino rats aged 2 months were divided into 3 equal groups. The control group 0,34 ml/kg/day saline; solving group 0,34 ml/kg/day olive oil; vitamin E group 40 mg/kg/day vitamin E (to be solved in the olive oil (0,26 ml/kg/day)) were treated for 30 days with a single daily intraperitoneal injections. After injections rats were tested for their ability to find the location of platform (spatial learning) during two phases: acquisition and retention phase. 1 week after tests of spatial learning, working memory was tested with the platform located in a different position. The time spent to find the platform and the time spent in half area of the tank including the platform in a value representing the percentage in the total time were compared statistically. There was no statistically significant difference at the time spent to find the platform and the time spent in half area of the tank including the platform among the group, while the time spent to find the platform was found to have increased from the first to the fourth day in all groups. These results indicate that the short period supplementation with vitamin E has not improved the performance in learning in the healthy young rats. It was concluded that the beneficial effect of vitamin E intake on learning is related with the beginning time and the duration of vitamin E intake

Anahtar Kelimeler

• Learning, memory, morris water maze, vitamin E, cognitive function

Kaynakça

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