Genetik absans epilepsili WAG/Rij sıçanlarda kardiyovasküler değişiklikler: Kronik etosüksimid tedavisinin etkileri

Amaç: Bu çalışmada, genetik absans epilepsili WAG/Rij sıçanlarda kronik etosüksimid (ETS) tedavisinin absans nöbetler ve gözlenebilecek olası kardiyovasküler değişiklikler üzerindeki etkilerinin araştırılması amaçlanmıştır.Gereç ve Yöntem: İki aylık erkek Wistar ve WAG/Rij sıçanlar; Wistar kontrol, Wistar ETS, WAG/Rij kontrol ve WAG/Rij ETS gruplarına ayrılmıştır (n=20). ETS grupları 3 ay boyunca kronik ETS tedavisi (oral, 300 mg/kg/gün) almışlardır. Üç aylık tedavi periyodunun sonunda EEG kayıtları kullanılarak diken dalga deşarjlarının (DDD) toplam süre, ortalama süre ve sayısı değerlendirilmiştir. Ortalama arteriyel kan basıncı (OAB) ve kalp hızı (KH) ölçümleri gerçekleştirilmiştir. Bulgular: ETS tedavisi WAG/Rij sıçanlarda DDD’leri toplam süre, ortalama süre ve sayı açısından anlamlı olarak azaltmıştır. OAB, WAG/Rij kontrol grubunda Wistar kontrol grubuna göre anlamlı olarak artmıştır. KH, Wistar ETS grubunda Wistar kontrol grubuna göre anlamlı olarak azalmıştır. KCl aracılı kasılma yanıtlarında Wistar kontrol grubuna göre Wistar ETS grubunda anlamlı artma, WAG/Rij kontrol grubunda anlamlı azalma saptanmıştır. Sonuç: Sonuçlarımız OAB ve vasküler reaktivitenin WAG/Rij sıçanlarda arttığını göstermiştir. ETS tedavisi, WAG/Rij sıçanlarda kardiyovasküler parametreleri değiştirmezken Wistar sıçanlarda KH ve vasküler reaktiviteyi azaltmış OAB’yi etkilememiştir. Bu değişikliklerde T-tipi Ca++ kanallarının rol oynayabileceği düşünülmektedir.

Cardiovascular changes in genetic absence epileptic WAG/Rij rats: Effects of chronic ethosuximide treatment

Purpose: The aim of this study was to investigate the effects of chronic ethosuximide (ETX) treatment on absence seizures and cardiovascular parameters in WAG/Rij rats with genetic absence epilepsy.Materials and Methods: Eight-weeks old, male Wistar and WAG/Rij rats were divided into four groups (n=20): Wistar control, Wistar ETX, WAG/Rij control and WAG/Rij ETX. ETX groups received chronic ETX treatment (oral, 300 mg/kg/day) for 3 months. At the end of the 3-month-treatment period; the total and mean duration, also number of spike wave discharges (SWDs) were evaluated using EEG recordings. Mean arterial blood pressure (MAP) and heart rate (HR) measurements were performed. Results: ETX treatment significantly decreased the duration and frequency of SWDs in WAG/Rij rats. MAP in WAG/Rij control group was markedly higher than Wistar control group. In Wistar ETX group, HR was significantly slower than Wistar control group. KCl-induced contraction response enhanced in Wistar ETX group and diminished in WAG/Rij control group compared to Wistar control group. Conclusion: Increased MAP and vascular reactivity in WAG/Rij rats. ETX treatment did not alter cardiovascular parameters in WAG/Rij rats whereas the treatment decreased the HR and vascular reactivity without affecting MAP in Wistar rats. T-type Ca++ channels may play a role in these changes.

Keywords:

Absence epilepsy WAG/Rij, ethosuximide, heart rate, blood pressure, vascular reactivity,

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