HİPOTİROİDİLİ SIÇANLARDA UZAMSAL ÖĞRENME PERFORMANSINDA CİNSİYET BAĞIMLI FARKLILIKLAR

Year 2017, Volume: 26 Issue: 3, 233 - 239, 01.12.2017

Ercan Babur , Burak Tan Nesrin Yıldız Melek Batakçı Cem Süer Nurcan Dursun

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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