LEYLA AYDIN, AYŞE ŞEBNEM İLHAN, MUSTAFA AGAH TEKİNDAL, Nimet Ünay GÜNDOĞAN

Stresli ve stressiz sıçanlarda fluoksetin hidroklorür kullanımının öğrenme ve bellek üzerine etkileri

Amaç: Bu çalışmada, stresin ve antidepresan ilaç tedavisinin sıçanlarda öğrenme ve bellek üzerine etkisinin araştırılması amaçlandı. Yöntem: 24 adet erişkin Wistar albino cinsi erkek sıçanlar, stresli- ilaçlı (GrupI), stresliilaçsız (GrupII), stressiz-ilaçlı (GrupIII) ve stressiz ilaçsız (GrupIV) olmak üzere rastgele 4 gruba ayrıldı. Stres oluşturmak için 16 °C suda 30 dakika bekletilen sıçanlara gavajla antidepresan olarak Fluoksetin hidroklorür 10 mg/kg/gün dozunda (FLX; Prozac) uygulandı. Öğrenme testleri Morris su tankında gerçekleştirildi. Sıçanlar tankta yüzdürülerek, sıçanların kaçış platformunu bulma süreleri incelendi. Bulgular: Grup I ve III’deki sıçanların günlere göre platformu bulma süreleri tutarlı bir şekilde azalırken Grup II’deki sıçanların tankta uzun süre hareketsiz kaldıkları, platformunu bulma sürelerinin düzensiz ve oldukça uzun olduğu tespit edildi. Grup IV’deki sıçanların günler arasında platformu bulma sürelerinde azalma çok belirgindi. Her grup içinde 34. günde kaçış platformunu bulma süreleri uzamıştı. 34. günde Grup IV’deki sıçanlarda strese bağlı hareketsiz kalma durumunun halen devam ettiği gözlendi. Sonuç: Stres altında olmadan fluoksetin hidroklorür kullanımının öğrenmeyi günlere göre anlamlı olarak, olumlu etkilediğini, stresli iken fluoksetin hidroklorür kullanımının ise stresin öğrenme üzerine olumsuz etkisini azalttığını ve strese bağlı durgunluk halini düzelttiğini tespit ettik. İlaç, bırakıldıktan 30 gün sonra, uzun süreli belleğin konsolidasyonu üzerinde etkili olmamıştır.

Effects of fluoxetine hydrochloride treatment on learning and memory in stressful and stress-free rats

Objective: In this study, it is aimed to investigate the effects of stress and antidepressant drug treatment on learning and memory in rats. Method: 24 male Wistar albino adult rats were randomly divided into four groups as stressful- medicated (Group I), stressful- drug-free (Group II), stress-free-medicated (Group III) stress-free-drugfree (Group IV). For stress model, rats were stayed in 16°C for 30 min. Fluoxetine hydrochloride (FLX; Prozac, 10mg/kg/day) by gavage as antidepressant. Learning tests were performed in Morris water maze. Rats were swam in the tank, the rats were investigated finding time the escape platform. Results: Time to find platform with respect to days was consistently decreased in Group I and III although in Group II rats were stayed immobile for a long time in maze and in this group time to find platform was irregular and too long. Decrease of time to find platform in Group IV was significant while the difference between other days was fewer. In day 34, time to find platform was prolonged within each group and staying immobile due to stress was remained. Conclusion: Use of fluoxetine hydrochloride in stress-free conditions significantly effects learning positively by day; in stressful conditions fluoxetine hydrochloride treatment decreased negative effects of stress on learning and impaired inactivity pattern. 30 days after quitting drug treatment, fluoxetine hydrochloride did not affect the consolidation of long-term memory.

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