Elif ÖZEROL, İbrahim ÖZEROL, MEHMET ASLAN, Mukaddes GÜLEÇ, Cengiz YAKINCI, Ömer AKYOL

Uzun süre sodyum valproat tedavisi alan epileptik çocuklarda plazma ve eritrosit nitrik oksit düzeyleri

Valproat (VPA), çocuklarda epilepsi tedavisinde yaygın olarak kullanılmaktadır. Nitrik oksit (NO), pek çok hücresel cevabı etkileyen önemli bir hücre içi fizyolojik mesajcıdır. Genellikle eritrosit membranının NO'e son derece geçirgen olduğuna inanılmaktadır. Literatürde VPA'nın antiepileptik etkisini NO üzerinden gösterebileceği iddia edilmektedir. Bu çalışmada, uzun süre VPA tedavisi alan çocuklarda plazma ve eritrosit NO konsantrasyonlarının sağlıklı kontrol bireyleri ile karşılaştırılması yanında plazma ve eritrosit NO düzeyleri ile VPA dozajı ve plazma konsantrasyonları arasında olası muhtemel ilişkiyi tayin etmek amaçlanmıştır. NO düzeyleri epilepsili 41 hasta ile 32 sağlıklı kontrolde ölçüldü. Total nitrit, endojen nitrik oksit üretiminin bir indeksi olarak Griess reaksiyonuyla ölçüldü ve sonuçların her biri diğeriyle karşılaştırıldı. VPA tedavisi altındaki epileptik çocuklarda hem eritrosit hem de plazma nitrik oksit düzeyleri kontrollerle karşılaştırıldığında herhangi bir farklılık olmadığı gözlendi. Her ne kadar VPA'nın antiepileptik etkisini NO üzerinden gösterebileceği iddia edilse de, bizim çalışmamız epilepsi ve VPA He uzun süre tedavinin plazma ve eritrosit NO konsantrasyonlarını etkilemediğini göstermiştir.

Anahtar Kelimeler:

Eritrositler, Antikonvülzanlar, Valproik asit, Nitrik oksit, Epilepsi

Plasma and erythrocyte nitric oxide levels in epileptic children receiving long-term sodium valproate therapy

Valproate (VPA) is a widely used drug as the first-line treatment for epilepsy in children. Nitric oxide (NO) is an important intercellular physiological messenger capable of evoking a number of cellular responses. It is generally believed that the erytrocyte membrane is highly permeable to NO. It has been claimed that VPA may show its antiepileptic effect throughout NO. Therefore, the aim of our study were to evaluate whether differences exist in the plasma and erythrocyte NO concentrations in children receiving long-term VPA in comparison with healthy control subjects and to determine the possible relationship between the plasma and erythrocyte NO levels and VPA dosage and their plasma concentrations.Levels of NO were measured in 41 patients with epilepsy and 32 healthy controls. Total nitrite was measured by Griess reaction as an index of endogenous NO production and results were compared with each other. The results showed that there were no differences both plasma and erytrocyte in nitric oxide levels in epileptic children on VPA therapy compared with the control group. In conclusion, although VPA has been suggested to show its antiepileptic effect via NO, our study demonstrates that epilepsy and prolonged treatment with VPA do not affect the levels of the plasma and erytrocyte NO concentrations.

Keywords:

Erythrocytes, Anticonvulsants, Valproic Acid, Nitric Oxide, Epilepsy,

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