Gözde Erkanlı ŞENTÜRK, Şükrü MİDİLLİOĞLU, Şehnaz BOLKENT, Serap ARBAK

Genetik Absans Epilepsili Sıçanların GAERS Hipokampusunda Glukoz–6-Fosfataz’ın Histokimyasal Olarak Dağılımı

Epilepsi tekrarlayan nöbetlerin varlığı ile belirgin ve sıklıkla geçici bilinç kayıplarına neden olan bir hastalıktır. Absans epilepsi modeli için kullanılan deney hayvanları olarak bilinen Genetik Absans Epilepsili Sıçanlar GAERS genetik olarak belirlenmiş nöbetler geçirmekte olup, 1980’li yıllardan itibaren insan absans epilepsi modelini teşkil edecek şekilde deneysel çalışmalarda kullanılmaya başlanmıştır. Bu çalışmada, absans epilepsi modeli için kullanılan GAERS sıçanlarda beyinde karbonhidrat metabolizmasında anahtar bir enzim olan glukoz-6-fosfataz aktivitesindeki değişiklik histokimyasal metotlarla araştırılmış ve hipokampusdaki glukoz metabolizması – glukoz-6-fosfataz – epileptogenez ilişkileri kontrol grubunu oluşturan Wistar albino sıçanlarla kıyaslanarak belirlenmeye çalışılmıştır. Kontrol gruplarında, epileptik olmayan Wistar albino Rattus norvecigus 4 aylık n: 4 , erkek, 220–240 gr ağırlığında sıçanlar kullanıldı. Deney gruplarında ise 6 aylık n: 4 , 250–300 gr ağırlığında, EEG’de absans nöbetler geçirdikleri belirlenmiş olan GAERS sıçanlar kullanıldı. Her iki deney grubunda hipokampusun Dentat Girus DG ve Cornu Ammonis CA bölgelerine glukoz–6-fosfataz histokimyası uygulandı. Kontrol grubu sıçanlara kıyasla GAERS sıçanlarda DG ve CA bölgelerinde glukoz–6-fosfataz reaktivitesinde bir artış olduğu enzim histokimyası uygulaması sonrası saptandı. Sonuç olarak, generalize konvulzif atakların glukoz kullanımını arttırdığının bilinmesinden yola çıkarak epilepsi vakalarında merkezi olarak verilecek glukoz–6- fosfatazın tedaviye yönelik olarak kullanımını destekler deneysel çalışmaların da ileride yapılabileceğini düşünmekteyiz

Histochemical Distribution of Glucose -6- Phosphatase In Hippocampus of Genetic Absance Epileptic Rats Gaers

Epilepsy is a disease with repeated seizures and usually caused transient ischemic attacks. Genetic Absence Epilepsy Rats from Strasbourg GAERS were recently used as a model for absence epilepsy. It has been used in experimental research in order to form the human absence epilepsy model since 1980. The aim of this study is to reveal changes in glucose–6–phosphatase activity which is the key enzyme of carbohydrate mechanism, at light microscopical levels by means of histochemical methods in GAERS’s brain. The correlation between the glucose metabolism and epileptogenesis has also been tried to be evaluated in this study. In control groups, non-epileptic Wistar albino, 4-months old, male, 220–240 gr rats were used n: 4 . Six-months old, 250–300 gr GAERS rats with previously determined absence seizures constituted the experimental group n: 4 Glucose–6-phosphatase histochemistry were examined within hippocampal Dentate Gyrus DG and Cornu Ammonis CA regions. Glucose–6–phosphatase reactivity were determined to be increased in DG and CA1 region in GAERS groups compared to the control group. As a result, based on the knowing generalized convulsive seizures increases the glucose utilization, glucose–6–phosphatase may be given in experimental studies, in order to treat with glucose–6–phosphatase in the cases of epilepsy in the future

Keywords:

glucose-6-phosphatase, GAERS, histochemistry,

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