HİPOTİROİDİLİ SIÇANLARDA UZAMSAL ÖĞRENME PERFORMANSINDA CİNSİYET BAĞIMLI FARKLILIKLAR

Abstract

Çalışmanın amacı, deneysel hipotiroidi (HT) geliştirilen sıçanlarda uzamsal öğrenme ve bellek bozukluklarının cinsiyet ile ilişkisini ortaya koymaktır. Hipotiroidi oluşturmada propiltiourasil (PTU) kullanılmıştır (0,2 mg/ kg, içme suları ile 21 gün). Öğrenme ve hafıza değişimlerini değerlendirmede Morris Su Tankı Testi kullanılmıştır. Test değerlendirmesi, anksiyete düzeyini ifade eden tigmotaksis oranı, HT grubunun kontrolden daha az anksiyete sergilediğini, Grup*Cinsiyet etkileşimi arasında ise önemli farklılığın olmadığını göstermiştir. Dişi sıçanların yüzme hızları erkek sıçanlara göre daha yavaş bulunmuştur. Öğrenme performansı değerlendirmesinde platforma ulaşma süresi, yüzme mesafesi ve platforma olan ortalama uzaklık değerlendirilmiştir. Kaçış mesafesi ve yüzme mesafesi değerlendirildiğinde hipotiroidi durumu platformu bulma süresini uzatmış, yüzme mesafesini arttırmıştır. Ancak cinsiyet faktörü hipotiroidideki bozulmaya etki etmemiştir. Yüzme hızından etkilenmeyen platforma olan ortalama uzaklık değerlendirildiğinde dişilerde öğrenme performansı anlamlı (p<0,001) bir şekilde azalmıştır ve hipotiroidi durumu bu azalmaya etki etmemiştir. Ayrıca tek başına hipotiroidi durumu platforma olan ortalama uzaklığı arttırmıştır. Post Hoc Tukey testine göre , hipotiroidili grupların kontrol gruplarına göre hedef kadranda daha az süre geçirdiği tespit edilmiştir (p<0,05). Ancak cinsiyet faktörü bu anlamlılığı etkilememiştir. Sonuç olarak hipotiroidi oluşturduğumuz hayvanlarda öğrenme ve hafıza performansının bozulduğu, hipotirodide görülen bu bozukluğa cinsiyet farklılığının bir etkisi olmadığı görülmüştür.

Keywords

• Hipotiroidizm, Sıçan, Öğrenme, Bellek, Morris Su Tankı

Gender-Dependent Differences on Spatial Learning Performance in Hypothyroid Rats

Abstract

The aim of the study was to investigate the effects of experimental hypothyroidism (HT) on spatial learning and memory disorders to establish relationship with gender. Propylthiouracil (PTU) was used to induce HT (0.2 mg / kg, 21 days with drinking water). Morris Water Tank test (MWTT) was used to evaluate learning and memory changes. When the anxiety level was expressed as the rate of tigmotaxis in the MWVT, it was found that the HT group was less anxious than the control group and there was no significant difference between the Group*Sex interaction. The swimming speed (SS) of female groups was found to be slower than the male groups. In evaluating the learning performance, the mean distance to platform (MdtoP), distance movement (DM) and escape latency (EL) was evaluated. During EL and DM assessment, the HT state prolonged the time to find the platform and increased swimming distance. However, the gender factor did not affect the deterioration of the HT state. Evaluating the MdtoP, which is not affected by SS, the learning performance in female was significantly reduced (p<0,001) and the HT state did not affect this decrease. In addition, hypothyroid status alone increased the mean distance to platform. According to the Post Hoc Tukey test, HT groups were realized that it spent less time than the control groups in target quadrant (p<0,05). However, the gender factor did not affect this significance. As a result, we found that the animals with hypothyroidism had poor learning and memory performance, and gender difference did not affect this deterioration in hypothyroidism.

Keywords

• Hypothyroidism, Rats, Learning, Memory, Morris Water Maze

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