Emin Şavik, Fatih Gültekin, İnanç Karakoyun, Duygu Kumbul Doğuç, Hilmi Demirin, Namık Delibaş

Klorpirifosun sıçanlarda öğrenmeye etkileri

Süleyman Demirel Üniversitesi TIP FAKÜLTESİ DERGİSİ: 2008 Mart; 15 (3) Klorpirifosun Sıçanlarda Öğrenmeye Etkileri Emin Şavik, Fatih Gültekin, İnanç Karakoyun, Duygu Kumbul Doğuç, Hilmi Demirin, Namık Delibaş Özet Amaç: Klorpirifosun (CPF) öğrenmeyi etkileyip etkilemediği ve öğrenmenin asetilkolin esteraz (AChE) düzeyleri ile ilişkisi çalışmamızda ortaya konulmaya çalışılmıştır. Gereç ve yöntem: Genç ve erişkin CPF grupları ve genç ve erişkin kontrol grupları olmak üzere 4 ana grup oluşturuldu. Tüm gruplar ışınsal kollulabirentte eğitildiler. Daha sonra CPF enjeksiyonu ve kontrol grubu enjeksiyonuna başlandı. Genç CPFgrubuna 40 mg/kg cilt altı, erişkin CPF grubuna 70 mg/kg cilt altı CPF enjeksiyonu yapıldı. Her grup kendiiçinde tekrar 2.gün, 7.gün ve 14.gün grubu olmak üzere ayrıldı. 2., 7. ve 14. günlerde ışınsal kollu labirentte öğrenme testleri yapılmıştır. Bu test bilgileri kullanılarak Seçim Doğruluğu ve Cevap Gecikmesi parametrelerihesap edilmiştir. Bununla beraber bu günlerde sıçanların AChE aktiviteleri çalışılmıştır. Bulgular: CPF, AChE düzeylerini erişkin sıçanlarda tüm günlerde, genç sıçanlarda ise 2. ve 7. günlerde anlamlı olarak düşürmüştür. Işınsal kollu labirentte Seçim Doğruluğu ve Cevap Gecikmesi üzerinde ise anlamlı bir değişikliğe neden olmamıştır. Sonuç: Uyguladığımız tek doz CPF ile AChE enzim inhibisyonunun genç ve erişkin sıçanlarda öğrenmeyi etkilemediği, dolayısıyla öğrenme ile direkt ilişkisinin olmayabileceği düşünülmüş; farklı doz ve uygulama süresi ile yeni çalışmaların yapılmasıyla daha açıklayıcı sonuçların elde edilebileceği kanaatine varılmıştır. Anahtar Sözcükler: Klorpirifos, Asetilkolin Esteraz, Radyal Kol Labirenti, Seçim Doğruluğu, Cevap Gecikmesi Abstract The effects of chlorpyrıfos on learnıng ın rats Aim: In this study we try to determine whether chlorpyrifos (CPF) administration affetcs the learning andrelation of learning with acetylcholine esterase (AChE) levels. Materials and methods: We arrange 4 maingroups as adult CPF, juvenile CPF, adult control and juvenile control group. Rats were trained on the workingmemory task in an eight arm radial maze. After acquisition they underwent enjections of CPF and controlgroup. Juvenile CPF group received 40 mg/kg CPF and adult CPF group received 70 mg/kg CPFsubcutaneously. Each group were seperated into 3 groups again as 2nd, 7th and 14th groups. Learning tests were applied by using radial arm maze on 2nd, 7th and 14th days. Choice Accuracy and Response Latencyparameters were calculated according to the data provided from these tests. Also AchE activities of rats werestudied on these days. Findings: CPF caused a significant increase in all of the adult rats where as on 2nd and7th days in juvenile ones. It did not cause any significant difference on Choice Accuracy and Response Latency. Results: It is concluded that the AChE inhibition of chlorpyrifos given at single dose did not affect the learning in juvenile and adult rats, therefore there is no direct relation between CPF and learning; the outcome is that future studies with different doses and administration durations may provide more explanatory results.

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