İçeri Doğrultucu Potasyum Kanalları ve Epilepsi

Year 2017, Volume: 14 Issue: 2, 141 - 149, 31.08.2017

Enes Akyüz , Pınar Mega Tiber

Abstract

İçeri doğrultucu potasyum kanalları “inwardly rectifying
potassium channels” (Kir kanalları), aksiyon potansiyelinde
hücre içine K+ iyonu taşıyarak, aksiyon potansiyelini
membran dinlenim potansiyeline stabilize etmekle
görevlidir. Yakın dönemde yapılan fonksiyonel
çalışmalarda, başta epilepsi olmak üzere çeşitli nörolojik
hastalıklarda ilişkisi olduğu belirlenen Kir kanallarının alt
ailelerinden olan Kir4.1 kanalının fonksiyon bozukluğuna
bağlı olarak hücre içine K+ iyonu taşıyamadığı görülmüştür.
Bu veriyi destekleyen araştırmalarda ise, ekstraselüler
ortamda glutamat ile K+ iyonu dengesinin bozulması
sonucu hücrenin hiperaktiviteye gidebileceği
düşünülmüştür. 7 alt aileye sahip Kir kanallarının epilepsi
mekanizmasındaki rolü üzerine yapılan araştırmalarda
şimdiye kadar Kir2.x, Kir3.x, Kir4.1 ve Kir6.2 kanallarının
fonksiyonel olarak değişebileceği gösterilmiştir. Klinik ve
deneysel araştırmalardan elde edilen kanıtların epilepsinin
kardiyak fonksiyonu etkileyebileceğini göstermektedir,
fakat bunun moleküler mekanizması henüz tam olarak
bilinmemektedir. Bu nedenle, ayrıca kardiyak Kir kanalları
da ele alınmıştır. 

Keywords

Kir kanalları, K+ iyonu, hiperaktivite, disfonksiyon, epilepsi

Inwardly Rectifying Potassium Channels and Epilepsy

Abstract

Inwardly rectifying potassium channels (Kir channels) are
responsible for restraining the action potential of the
membrane by stabilizing the membrane potential for
relaxation by transporting K+
ions into the cell. Recent
functional studies have shown that the Kir4.1 channel, a
subset of the Kir channels, which is associated with various
neurological disorders, primarily epilepsy, cannot carry K+
ions into the cell due to dysfunction. In studies supporting
this data, it was thought that the glutamate and K+
ion
unbalance in the extracellular medium could result in
hyperactivity of the cell. Investigations into the role of Kir
channels with 7 subfamilies in the mechanism of epilepsy
have shown that the Kir2.x, Kir3.x, Kir4.1 and Kir6.2
channels functionally may change. Evidence obtained from
clinical and experimental studies show that epilepsy could
affect cardiac function; however, the molecular mechanism
underlying has not been fully understood yet. For this
reason, cardiac Kir channels are also considered. 

Keywords

Kir channels, K+ ion, hyperactivity, dysfunction, epilepsy

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