FLUVASTATİNİN TAVŞAN KAROTİD ARTERİ YAKA MODELİNDE İNTİMAL KALINLAŞMA ÜZERİNE ETKİLERİ

Öz

Amaç: Statinlerin LDL-kolesterol düşürücü etkilerinden bağımsız endotel fonksiyonu gibi aterosklerozun pek çok bileşeni üzerinde de etkileri mevcuttur. Bu etkileri pleiotropik etkileri olarak da bilinmektedir. Bu çalışmada fluvastatinin normokolesterolemik tavşanlarda intimal kalınlaşma üzerine etkisinin araştırılması planlanmıştır.

Gereç ve Yöntem: Çalışmada Yeni Zelanda tavşanlarına 3 hafta boyunca fluvastatin (8 mg/kg/gün oral) ve plasebo tedavi uygulandı. Tedavinin sekizinci gününde okluzif olmayan silikon bir yaka sol karotid arterinin çevresine yerleştirilerek on dört gün daha tedaviye devam edildi. Deney sonunda sağ ve sol karotid arterler çıkarıldı. Çıkarılan karotid arterlerden alınan kesitlerde morfometrik ölçümler gerçekleştirildi. İntima, medya, lümen ve eksternal elastik lamina alanları ölçülerek indeks, rezidüel lümen oranı değerleri hesaplandı.

Bulgular: Yaka intimal alan ve indeks değerinde belirgin bir artışa ve RLO değerinde azalmaya neden olurken fluvastatin yakanın neden olduğu intimal kalınlaşmayı inhibe etti.

Sonuç: Bulgularımız fluvastatinin kolesterol düşürücü etkisinden bağımsız aterosklerozun erken döneminde de yararlı etkileri olabileceğini göstermektedir.

Anahtar Kelimeler

• fluvastatin
• statin
• intimal kalınlaşma
• yaka modeli
• karotid arteri

Effects of fluvastatin on intimal thickening in rabbit carotid artery collar model

Abstract

Objective: Statins may exert effects that are independent of LDL-cholesterol lowering on many components of atherosclerosis including endothelial function, called pleiotropic effects. In this study we aimed to investigate effects of fluvastatin on intimal thickening in normocholesterolemic rabbits.

Materials &Method: New Zeeland rabbits were treated with fluvastatin (8 mg/kg/day, p.o.) and placebo for 3 weeks. On the 8th day, a non-occlusive silicon collar was positioned around the left carotid artery for 14 days and then both carotid arteries were isolated. Intimal, medial, lumen and external elastic lamina cross sectional areas were measured by computer based morphometric analysis and index (intima/media), residual luminal ratio (RLR) values were calculated.

Results: Collar caused significant increase in intimal area, index values and decrease in RLR values. Fluvastatin treatment significantly inhibit collar-induced intimal thickening.

Conclusion: These findings indicate that fluvastatin may have beneficial effects on the early stages of normocholesterolemic atherosclerosis.

Keywords

• fluvastatin
• statins
• intimal thickening
• collar
• carotid artery

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