Özlem COŞKUN, Ozlem OZTOPUZ, Turgay ÇOKYAMAN

Deneysel epilepsi modelinde KCNQ1 ve KCNQ3 genlerinin ekspresyon düzeyleri

Amaç: Status epileptikus (SE) 30 dakikadan daha uzun süre tekrarlayan jeneralize konvulziyonlarla birlikte çocuklarda oldukça yaygın bir şekilde görülen nörolojik bir hastalıktır ve kontrol edilmediğinde, beyinde nöronal hasarlar meydana gelir. Bu çalışmanın amacı SE sonrası akut dönemde KCNQ1 ve KCNQ3 gen ekspresyon seviyelerindeki değişiklikleri değerlendirmektir. Gereç ve Yöntem: Sıçanlarda Li-Pc ile deneysel SE modeli oluşturuldu. Çalışmada; SE, kontrol ve sham grupları olmak üzere 3 grupta dişi Wistar albino [250–350 gr, 21 adet (n=7)] sıçan kullanıldı. Beyin dokularından elde edilen total RNA, cDNA'ya çevrilerek KCNQ1 ve KCNQ3 genlerinin kantitatif gerçek zamanlı PCR (qRT-PCR) yöntemi ile gen ekspresyon değişimleri değerlendirildi. Bulgular: İstatistiksel olarak SE grubunda; kontrol ve sham grubuna kıyasla KCNQ1 ve KCNQ3 genlerinin ekspresyon seviyelerinde anlamlı oranda farklılık görüldü. Deney grubunun KCNQ1 ve KCNQ3 gen ekspresyon düzeyleri diğer gruplardan yüksek bulundu. Sonuç: K+ iyon kanallarını kodlayan genlerin mRNA ekspresyon seviyelerindeki değişikliklerin belirlenmesi epilepsi sırasında oluşan patolojik mekanizmaların daha iyi anlaşılmasına yardımcı olacaktır. Oluşturulan SE deneysel modelde KCNQ1 ve KCNQ3 mRNA ekpresyonlarında artış saptanması ileride yapılması planlanan tedaviye yönelik ilaç çalışmalarına yol göstereceğine inanılmaktadır.

Expression levels of KCNQ1 and KCNQ3 genes in experimental epilepsy model

Purpose: Status epilepticus (SE) is a highly common neurological disease in children, with recurrent generalized convulsions for more than 30 minutes, and when not controlled, neuronal damage occurs in the brain. The aim of this study was to evaluate the changes in KCNQ1 and KCNQ3 gene expression levels in the acute period after SE. Materials and Methods: In rats, an experimental SE model was created with Li-Pc. Study; female Wistar albino [250–350 g, 21 (n=7)] rats were used in 3 groups as SE, control and sham groups. The total RNA obtained from brain tissues was converted to cDNA, and gene expression levels of KCNQ1 and KCNQ3 genes were assessed by quantitative real-time PCR (qRT-PCR) method. Results: Statistically in SE group; compared to the control and sham groups, a significant difference was observed in the gene expression levels of the KCNQ1 and KCNQ3 ion channels. The KCNQ1 and KCNQ3 gene expression levels of the experimental group was found higher than the other groups. Conclusion: Determining the changes in mRNA expression levels of genes encoding K+ ion channels will help to better understand the pathological mechanisms that occur during epilepsy. In the SE experimental model created, it is believed that an increase in mRNA expression of KCNQ1 and KCNQ3 will lead to drug therapy studies planned for the future.

Keywords:

epilepsy status epilepticus, KCNQ1, Li pilocarpine,

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