EFFECTS OF AGMATINE SUPPLEMENTATION AND AEROBIC EXERCISE ON SPATIAL LEARNING IN AGED RATS

Öz

OBJECTIVE: The aim of the study is to examine the effects of agmatine supplementation and exercise on cognitive functions of aged rats.
MATERIAL AND METHODS: In the study, 36 healthy, old male Sprague-Dawley rats with a weight of 300-350 gr were used. The rats were randomly divided into as control (n=6), exercise (n=10), agmatine (n=10), agmatine+exercise (n=10) groups. The rats in the control group and the exercise group were administered 1 mg / kg (i.p) saline for 8 weeks. 40 mg/kg (i.p) Agmatine supplementation was given to the rats at the agmatine groups. Swimming exercise was applied for 8 weeks to the exercise and agmatine+exercise groups. At the end of the 8th week, Morris maze test was concluded. All the animals were decapitated and the blood and tissue samples (hippocampus) were taken for measuring brain derived neurotrophic factor (in plasma), the agmatine and nitrite+nitrate levels in hippocampus. Protein concentration was determined by the Lowry method.
RESULTS: Agmatine level was significantly higher in the agmatine and agmatine+exercise groups compared to the control group and exercise group (p<0.05). In terms of the brain derived neurotrophic factor (BDNF) and nitrite+nitrate levels there was no significant difference between the groups (p<0.05). On the first day and fourth day, there was no difference between the groups in terms of total logged distance and durations of finding the platform at the phase of Morris water maze test (p<0.05). On the second day and third day, the total logged distance and durations of finding the platform was lower in the agmatine+exercise group compared to the control group (p<0.05).
CONCLUSIONS: It was observed that agmatine supplementation might have positive effects on spatial learning in aged rats.

Anahtar Kelimeler

• Agmatine,
• Brain derived neurotrophic factor
• Exercise
• Learning

YAŞLI SIÇANLARDA AGMATİN TAKVİYESİ VE AEROBİK EGZERSİZİN UZAYSAL ÖĞRENME ÜZERİNE ETKİSİ

Öz

AMAÇ: Çalışmanın amacı, yaşlı sıçanlarda agmatin takviyesi ve egzersizin kognitif fonksiyonlar üzerine etkilerinin incelenmesidir.
GEREÇ VE YÖNTEM: Çalışmada, 300-350 gr ağırlığında, 36 adet sağlıklı yaşlı erkek Sprague-Dawley sıçan kullanıldı. Sıçanlar rastgele olarak kontrol (n=6), egzersiz (n=10), agmatin (n=10), agmatin+egzersiz (n=10) gruplarına ayrıldı. Kontrol grubunda ve Egzersiz grubunda yer alan sıçanlara 8 hafta 1 mg/kg (i.p) serum fizyolojik uygulandı. Agmatin gruplarında bulunan sıçanlara 8 hafta 40 mg/kg (i.p) agmatin takviyesi uygulandı. Egzersiz ve agmatin+egzersiz gruplarına 8 hafta boyunca yüzme egzersizi uygulandı. 8. haftanın sonunda Morris su labirent testi gerçekleştirildi. Tüm hayvanlar dekapite edildi ve beyin kaynaklı nörotrofik faktör (plazmada), hipokampuste agmatin ve nitrit+nitrat seviyelerinin ölçümü için kan ve doku (hipokampus) örnekleri alındı. Protein konsantrasyonu Lowry metoduyla tayin edildi.
BULGULAR: Agmatin seviyesi agmatin ve agmatin+egzersiz gruplarında kontrol grubu ve egzersiz grubuna göre belirgin şekilde yüksekti (p<0.05). Beyin kaynaklı nörotrofik faktör (BDNF) seviyesi ve nitrit+nitrat seviyeleri bakımından gruplar arasında belirgin bir fark yoktu (p<0.05). Morris su labirent testi deneme fazında 1. gün ve 4. gün gruplar arasında toplam kat edilen mesafe ve platformu bulma süreleri açısından fark yoktu (p<0.05). 2. gün ve 3. gün toplam kat edilen mesafe ve platformu bulma süreleri kontrol grubuna göre agmatin+egzersiz grubunda daha düşüktü (p<0.05).
SONUÇ: Agmatin takviyesinin yaşlı sıçanlarda uzaysal öğrenme üzerine olumlu etkileri olabileceği gözlemlendi.

Anahtar Kelimeler

• Agmatin
• Beyin kaynaklı nörotrofik faktör,
• Egzersiz
• ,Öğrenme

Kaynakça

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