Atilla SARAÇ, Levent YILDIZ, Hasan Tahsin KEÇELİGİL, Hacı AKAR, Ferşat KOLBAKIR

Karnitin ve C vitamininin reperfüzyon hasarına olan etkilerinin araştırılması

Askorbik asit güçlü indirgeyici aktivitesinden dolayı, güçlü bir antioksidandır. Süperoksit ve hidroksil radikali ile kolayca reaksiyona girerek onları temizler. Karnitin ise beta oksidasyonları için uzun zincir yağ asitlerinin mitokondrial matriks içine taşınmasını sağlar ve reperfüzyon döneminde glikoz oksidasyonunu artırır. Bu iki ajanın antioksidan etkisi tavşanda ekstremite iskemi / reperfüzyon modelinde araştırıldı. Reperfüzyon sonrası tüm deneklerin soleus kasından alınan segmenter kas biyopsisi örnekleri ışık mikroskobunda iskemik hasarın patolojik bulguları olan nekroz, striasyon kaybı, santralizasyon, splitting veya ring formasyonu, fibrozis ve çap farklılıkları açısından değerlendirilerek, gruplar arasında istatistiksel fark olup olmadığı araştırıldı. Uygulanan deneysel modelde, sodyum askorbat verilen grupta istatistiksel olarak anlamsız, karnitin verilen grupta ise istatistiksel olarak da anlamlı olmak üzere serum fizyolojik verilen kontrol grubuna göre reperfüzyon hasarında azalma görüldü. Karnitin ve sodyum askorbat verilen gruplar kendi aralarında karşılaştırıldıklarında ise fibrozis ve çap farkı açısından istatistiksel olarak da anlamlı olmak üzere tüm parametrelerde karnitinin iskemik hasarın azaltılmasında daha etkili olduğu gözlemlendi.

Comparison of effects of carnitin and ascorbic acid on reperfusion injury

Because of its reducing effect, ascorbic acid , is a strong antioxidant agent and has the ability of reacting with superoxide anion and hydroxyl ion of oxygen-derived free radicals. Carnitine also can increase the oxidation of glucose during the reperfusion phase by performing transportation of long chain fatty acids to the mitochondrial matrix for the beta oxidation. Antioxidant effects of these substances were studied on rabbits at the basis of extremity ischemia / reperfusion ( I/R) model. Following reperfusion biopsies were taken from soleus muscles. All of the biopsy specimens were looked under light microscope from the aspect of histopatologic findings of ischemic injury which were necrosis, loss of striation, centralization, splitting / ring formation, fibrosis and diameter differences, and results were analyzed statisticaly. Data have showed that both sodium ascorbate and carnitine were effective in reducing the reperfusion injury when compared to the placebo group. Differences were insignificant for sodium ascorbate and sinificant for carnitine statisticaly. Compared to each other, carnitine was superior to sodium ascorbate but the difference was significant statisticaly only from the aspect of fibrosis and diameter differences.

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