Nazmi NARİN, Abdulhakim COŞKUN, Abdulkerim COŞKUN, Figen NARİN, Sertaç Hanedan ONAN, Ruşen EREZ, Ali BAYKAN, Muammer Hakan POYRAZOĞLU

An investigation of changes in ocular blood fl ow in rabbits with long-term hyperhomocysteinemia using color doppler ultrasonography

Amaç: Bu çalışmada, tavşanlara metionin verilerek oluşturulan hiperhomosisteineminin oküler kan akımı üzerindeki etkilerini renkli Doppler ultrasonografi kullanarak araştırdık. Yöntem ve gereç: Toplam 50 Yeni Zelanda tavşanı beş gruba ayrıldı. Grup 1-4’e sırasıyla; sadece metionin, metionin ve B6 vitamini, metionin ve B12 vitamini, metionin ve folik asit uygulandı. Kontrol grubunun diyetine kimyasal madde eklenmedi. Serum homosistein seviyeleri tedavinin 1. ve 60. günlerinde çalışıldı. Orbital damarlar 60. günde renkli Doppler ultrasonografi ile değerlendirildi. Bulgular: Çalışma gruplarının dördünde homosistein seviyeleri 60. günde 1. günden anlamlı şekilde yüksekti (P < 0,05). 60. günde homosistein seviyesindeki yükselme Grup 1’de Grup 2 ve 4’den fazla idi. Oküler arter akım hızlarındaki değişiklikler karşılaştırıldığında gruplar arasında istatistiksel olarak anlamlı fark gözlenmedi. Çalışma gruplarında silier arterin akım hızlarında istatistiksel olarak anlamlı düzeyde azalma izlendi (P < 0,05). Sonuç: Renkli Doppler Ultrasonografi kullanarak silier arterde kan akım hızlarının azaldığını gösterdik. Bu durum, hiperhomosisteinemiden dolayı oküler damarlarda gelişen aterosklerotik ve tromboembolik değişiklere dayandırılabilir.

Uzun dönem hiperhomosisteinemili tavşanlarda oküler kan akımı değişikliklerinin renkli doppler ultrasonografi ile araştırılması

Aim: Hyperhomocysteinemia was induced in rabbits using methionine. Ocular blood flow changes were examined by color Doppler ultrasonography (CDU). Materials and methods: Fifty New Zealand rabbits were divided into 5 groups. Groups 1-4 received one of the following chemicals: methionine only, methionine plus vitamin B6, methionine plus vitamin B12, or methionine plus folic acid. Controls received no chemicals. Serum homocysteine levels were measured on treatment days 1 and 60. Orbital vessels were examined by CDU on day 60. Results: In the 4 study groups, homocysteine levels were significantly elevated on day 60 compared to the levels on day 1 (P < 0.05). Elevations of homocysteine levels in group 1 were greater than those of groups 2 and 4 on day 60 (P < 0.05). When results of ocular blood flow changes were compared, no statistically significant difference was found based on flow velocities in the ophthalmic artery. Measurements from the ciliary artery revealed a statistically significant decrease in flow velocity in the study groups (P < 0.05). Conclusion: Using CDU, we found that flow velocities in the ciliary artery were decreased. This condition is attributed to atherosclerotic and thromboembolic alterations of the ocular vessels due to hyperhomocysteinemia.

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