Fatmah Bibi Housnah GURIB, Anwar Hussein SUBRATTY

Homocysteine potentiates esterase-induced contraction on rat aorta in vitro: A risk factor for atherosclerosis

Bu çalışmada, homosistein etkisi altında N-α- l-tosil arginin metil ester (TAME) ile arttırılmış sıçan thoracic aortunda in vitro kasılmayı nasıl etkilediği araştırılmıştır. Aort izole edilerek Krebs çözeltisi içeren bir organ banyosuna yerleştirilmiştir. Değişik konsantrasyonlarda $(10^{-15}-10^{-1}M)$ TAME çözeltisinde kesik aort stripleri test edilmiştir. TAME etki ettirilmiş bu striplerde ayrıca homosistein etkisi araştırılmıştır. Bulunan sonuçlara göre konsantrasyona bağlı TAME etkili kasılmanın önceden homosistein ile inkübe edilen striplerde görülen kasılmaya göre daha göze çarpıcı olduğu saptanmıştır.

Homosisteinin sıçan aortunda esteraz ile arttırılan in vitro kasılmayı güçlendirmesi: Athereosclerosis oluşumu için bir risk faktörü

The present study was designed to investigate the effect of homocysteine on N-α- l-tosyl arginine methyl esterinduced contraction of rat thoracic aorta in vitro. Aorta was isolated and mounted in an organ bath containing Krebs solution. The effect of TAME was tested on intact aortic strips by challenging with different concentrations of TAME $(10^{-15}-10^{-1}M)$ . The effects of homocysteine were also investigated on TAME-induced contraction on rat aorta strips. Our data showed that the concentration dependent TAME-induced contraction were more prominent when rat aortic strips were pre-incubated with homocysteine.

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