Aşırı Uyarılabilirlik Koşullarında Gap-Junction İnhibisyonunun Yüksek Frekanslı Salınımlar Üzerine Etkisi: In Vitro Elektrofizyolojik Bir Çalışma

Year 2025, Volume: 26 Issue: 3, 257 - 262, 22.09.2025

Hilal Öztürk

https://doi.org/10.69601/meandrosmdj.1681110

Abstract

Amaç: Beynin elektriksel aktivitesinin 80-500 Hz arasındaki frekans bandını kapsayan Yüksek Frekanslı Salınımlar (HFO), epileptik nöbetler için bir belirteç olarak kabul edilir. Korteksteki boşluk-bağlantıların HFO'lara katkısını araştırdık.
Yöntemler: HFO'lar iki farklı frekans bandında araştırıldı: 80-200 Hz dalgalanma ve 250-500 HZ hızlı dalgalanma olarak kabul edildi. HFO'lar, taze beyin dilimlerinde 4AP kaynaklı nöbetlerin elektrofizyolojik kayıtlarından tespit edildi. Daha sonra boşluk-bağlantısı blokerleri uygulandı ve HFO'ların gücü üzerindeki etkileri takip edildi. Bir konneksin blokeri olan Flufanemik asit (100 μM, n=10) ve bir panneksin-1 blokeri olan Probenesid'in (200 μM, n=8) etkileri analiz edildi. İlgili frekans aralıklarının güç spektrumu analizleri yapıldı. Blokörlerin 0-40 Hz frekansındaki etkileri de analiz edildi.
Bulgular: Flufenamik asit 0-40 Hz frekans bandı ve dalgalanma deşarjlarını önemli ölçüde azalttı ve hızlı dalgalanmalar üzerinde hiçbir etkisi olmadı. Probenesid uygulaması 0-40 Hz, dalgalanma ve hızlı dalgalanma frekans aralığını azalttı ancak anlamlı ölçüde değiştirmedi.
Sonuçlar: Bu, iki boşluk bağlantı blokeri olan flufenamik asit ve probenesidin aynı deneysel koşullar altında uygulandığı ve etkinliklerinin birbirleriyle karşılaştırıldığı ilk çalışmadır. HFO son yıllarda birçok çalışmanın konusu olmuştur. Bu salınımların ve başlangıç bölgelerinin tespiti, gelişecek nöbet hakkında derin bilgiler sağlar. Gelecekteki çalışmalar epilepsi hastalığındaki cevapsız sorulara ışık tutacak ve nöbet patogenezinin ve yeni tedavi yöntemlerinin geliştirilmesine katkıda bulunacaktır.

Keywords

Boşluk-bağlantı , yüksek frekanslı salınımlar , beyin kesitleri

Effect of Gap-Junctıon Inhıbıtıon on High-Frequency Oscillations Under Hyperexcitability: An In Vitro Electrophysiological Study

Abstract

Objective: High Frequency Oscillations (HFO), covers the frequency band between 80-500 Hz component of the electrical activity of brain, is considered a marker for epileptic seizures. We investigated the contribution of gap-junction to HFOs in cortex.
Methods: HFOs were investigated in two different frequency bands: 80-200 Hz accepted as ripple and 250-500 HZ as fast ripples. HFO’s detected from electrophysiological recordings of 4AP-induced seizures in fresh brain slices. Then, gap-junction blockers were applied and their effects on power of HFOs were followed. Effects of Flufanemic acid (100 μM, n=10), a connexin blocker, Probenecid (200 μM, n=8), a pannexin-1 blocker, were analyzed. Power spectrum analyses of the relevant frequency ranges were performed. The effects of the blockers on 0-40 Hz frequency also analyzed.
Results: Flufenamic acid significantly reduced 0-40 Hz frequency band and ripple discharges, and had no effect on fast ripples. Probenecid application reduced the 0-40 Hz, ripple and fast ripple frequency range, but did not change significantly.
Conclusion: This is the first study in which two gap junction blockers, flufenamic acid and probenecid, were applied under the same experimental conditions and their effectiveness was compared with each other. HFO has been the subject of many studies in recent years. The detection of these oscillations and their onset regions provide deep information about the seizure that will develop. Future studies will shed light on unanswered questions in epilepsy disease and contribute to the development of seizure pathogenesis and new treatment methods.

Keywords

Gap-junction , High frequency oscillation , brain slices

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