Dentat Girus İçerisine İnfüze Edilen T4'ün Uzun Dönemli Etkinleşme Yanıtları Üzerine Etkisi ve Mitojen İle Aktive Olan Protein Kinazın Rolü

Yıl 2020, Cilt: 30 Sayı: 1, 16 - 23, 01.03.2020

Burak Tan Ercan Babur Arzu Dilek Güler Cem Süer Nurcan Dursun

Öz

Amaç: Bu çalışmada tiroksin hormonunun uzun dönemli güçlenme UDG yanıtları, N-metil-D aspartat NMDA reseptörü ve P38-Mitojenle Aktive Olan Protein Kinaz P38 MAPK üzerine olan etkisinin araştırılması amaçlanmıştır.Gereç ve Yöntem: Çalışma, 2-4 aylık erkek ve dişi Wistar albino sıçanlar üzerinde yapıldı. Sıçanlar üretan anestezisi altında stereotaksik çatıya yerleştirildi. Alan potansiyelleri perforan yolun uyarılmasına yanıt olarak dentat girustan kaydedildi. Bazal alan potansiyellerini takiben 15 dk süre ile hipokampüse tiroksin infüzyonu yapıldı. İnfüzyonu takiben 100 Hz frekanslı uyarım 5 dakika ara ile 4 kez uygulandı. Son tetanik uyarımdan 60 dakika sonra sıçanların hipokampüsleri çıkarıldı. Hipokampüs örneklerinden NR1, NR2A, NR2B ve P38 MAPK'a ait gen anlatımlarının incelenmesi gerçek zamanlı kantitatif polimeraz zincir reaksiyonu RT-qPCR yöntemi ile yapıldı.Bulgular: Yüksek frekanslı uyarım verilmesi esnasında tetiklenen populasyon spike PS genliği ve eksitatör post sinaptik potansiyel EPSP eğiminin, tiroksinin hipokampüse infüze edilmesiyle her iki cinsiyette kontrole göre azaldığı belirlendi. Bununla uyumlu olarak, NR2B ve P38 MAPK düzeyleri için her iki cinsiyette kontrole göre artış olduğu belirlendi.Sonuç: Çalışma bulguları, tiroksin infüzyonunun sinaptik plastisiteyi inhibe ettiği ve bu inhibisyona NR2B ve P38 MAPK ekspresyonundaki değişimlerin aracılık ettiğine dair kanıtlar sunmaktadır

Anahtar Kelimeler

Tiroksin, uzun dönemli güçlenme, hipokampüs

Dentate gyrus T4 infused into activation response effect of long-term, and mitogen-activated protein kinase role

Öz

Objective: In the present study, it was aimed to investigate the effect of the L-thyroxine hormone on long-term potentiation LTP responses, N-methyl-D aspartate NMDA receptor and P38-mitogen-activated protein kinase P38 MAPK .Material and Method: The study was performed on 2-4 month old male and female Wistar albino rats. Rats were placed onto stereotaxic roof under anesthesia. Field potentials were recorded in dentate gyrus in response to perforant pathway stimulation. Hippocampal thyroxine infusion was performed for 15 min following basal field potentials. Following infusion, 100 Hz frequency stimulation was applied 4 times with 5 min intervals. After 60 minutes from the last tetanic stimulation, the hippocampus of the rats was removed. Examination of gene expression of NR1, NR2A, NR2B and P38 MAPK from hippocampal samples was performed by real-time quantitative polymerase chain reaction RT-qPCR method.Results: It has been determined that the population spike PS amplitude and the excitatory post synaptic potential EPSP triggered during high frequency stimulation are reduced in both sexes by hippocampal infusion of thyroxine.Conclusion: The findings of the study provide evidence that the infusion of thyroxine inhibits synaptic plasticity and that this inhibition is mediated by changes in NR2B and P38 MAPK expression

Anahtar Kelimeler

Thyroxine, long term potentiation, hippocampus

Kaynakça

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