The effects of stress and menopause on learning

Yıl 2019, Cilt: 12 Sayı: 2, 210 - 219, 30.08.2019

Mehmet Berköz Fatma Rezan Hatungil Ali Erdinç Yalın Ülkü Çömelekoğlu Serap Yalın Hüseyin Beydağı Bora Reşitoğlu Nefise Özlen Şahin Pelin Eroğlu

https://doi.org/10.26559/mersinsbd.489911

Öz

Aim: In
this study, we aimed to to investigate the co-effect of stress and menopause on
the learning ability in rats. Methods: 60 female Wistar-Albino
rats were used in this study and were
randomly divided into four groups (15 rats per group) as follows: Control group
(Group I), experimental immobilization stress model (Group II), experimental
menopause model (Group III), and experimental menopause model + experimental
stress model (Group IV). Long-term cognitive and motor abilities of all rats
were evaluated by conducting behaviour experiments (open field and morris water
maze test). Furthermore, the gene expression of corticosteroid receptor
(glucocorticoid receptor and mineralocorticoid receptor) was
examined by Real-Time PCR using SYBR Green followed by mRNA isolation and cDNA
synthesis. Results: In the comparison study of
in-group time for attaining mean elevation over days, it was detected that time
for attaining mean elevation was statistically significantly shorter than
previous day from 1^st day to 4^th(p<0.001). There was no statistically
significance for daily time for mean elevation among the groups (p>0.05). In
the open area experiment, although the Group II exhibited shorter mean when
comparing the progressed distances, but the difference among the groups was not
statistically significant (p>0.05). Gene expression of both glucocorticoid
receptor and mineralocorticoid receptor in the hipocampal tissue was determined
to be lower in comparison with the control group. However, this decrease was
not statistically significant (p>0.05). Conclusion: This
result shows that acute immobilization stres and experimental menopause model
is not efficient on the learning ability in rats. 

Anahtar Kelimeler

Stress, menopause, learning, hypothalamus-pituitary-adrenal axis

Stres ve menopozun öğrenme üzerindeki etkileri

Öz

Amaç: Bu
çalışmada stres ve menopozun birlikte, öğrenme işlevi üzerindeki etkileri
araştırılmıştır. Yöntem: Çalışmada,
60 adet dişi Wistar-Albino sıçan kullanılmıştır. Bu sıçanlar randomize olarak kontrol
(Grup I), deneysel immobilizasyon stres modeli (Grup II), deneysel menopoz
modeli (Grup III) ve deneysel menopoz modeli + deneysel stres modeli (Grup IV)
olmak üzere her bir
grupta 15’er hayvan bulunan 4 gruba ayrılmıştır. Tüm sıçanların uzun dönemdeki
bilişsel ve motor yetileri davranış deneyleri (açık alan ve Morris su tankı)
ile değerlendirilmiştir. Ayrıca hipotalamus-hipofiz-adrenal ekseninin
geribildirim işlevinde merkezi konumunda olan kortikosteroid reseptör
(Glukokortikoid reseptörü ve mineralokortikoid reseptörü) gen ekspresyonu mRNA
izolasyonu ve cDNA sentezi takibinde SYBR Green kullanılarak eş zamanlı PCR
yöntemiyle incelenmiştir. Bulgular: Tüm grupların kendi içinde günlere göre ortalama
yükseltiyi bulma sürelerinin karşılaştırmasında, birinci günden 4. güne kadar,
tüm gruplarda her günün ortalama yükseltiyi bulma sürelerinin bir önceki günden
istatistiksel olarak anlamlı düzeyde kısa olduğu saptanmıştır (p<0.001).
Güne göre yükseltiyi bulma sürelerinin gruplar arasında karşılaştırmasında
istatistiksel olarak anlamlı bir fark saptanmamıştır (p>0.05). Açık alan
deneyinde ortalama katedilen mesafenin gruplara göre karşılaştırmasında grup II
en düşük ortalamaya sahip olmasına karşın, gruplar arasında istatistiksel olarak
anlamlı bir fark bulunamamıştır (p>0.05). Hipokampal dokuda hem glukokortikoid
reseptörünün hem de mineralokortikoid
reseptörünün gen ekspresyonu tüm gruplarda
kontrol grubuna kıyasla düşük bulunmuştur. Ancak bu düşüş istatistiksel olarak
anlamlı bulunamamıştır (p>0.05). Sonuç:
Bu sonuç akut immobilizasyon stresin ve deneysel menopoz modelinin öğrenme
üzerinde etkili olmadığını düşündürmüştür.

Anahtar Kelimeler

Stres, menopoz, öğrenme, hipotalamus-hipofiz-adrenal aksı, kortikosteroid reseptörleri

Kaynakça

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