Haşim ÜSTÜNSOY, Hakkı KAZAZ, Mehmet Adnan CELKAN, Sevgi ÇAVDAR, İbrahim SARI

Sıçan iskemi-reperfüzyon modelinde iskemik önkoşullamanın miyokardiyal apoptoza etkisi

Amaç: İskemik hücresel hasarlanmayı önlemek veya azaltmak için geliştirilen yaklaşımlardan biri iskemik önkoşullamadır. Bu sıçan modelinde iskemik önkoşullamanın miyokardiyal apoptoz üzerine etkisi araştırıldı. Çalışma planı: Çalışmada 30 adet Wistar cinsi erkek sıçan kullanıldı. Sıçanlara sol torakotomi yapıldıktan sonra kalp serbestleştirildi. Kontrol grubundaki 10 sıçana ek bir işlem uygulanmadı. İskemi grubundaki 10 sıçana sol ana koroner arterde 30 dakika oklüzyon (iskemi), arkasından 120 dakika reperfüzyon uygulandı. Önkoşullama grubundaki 10 sıçana ise bu işlemler öncesinde 5 dakika iskemi, 5 dakika reperfüzyon uygulandı. Deneyler sonrasında kalpler çıkarılarak, hazırlanan kesitlerde bcl-2 immünhistokimyasal boyama yöntemiyle bcl-2 indeksi belirlendi.Bulgular: bcl-2 immünhistokimyasal boyama yöntemiyle, infarkt alanındaki apoptotik hücre oranı iskemik önkoşullama yapılan grupta %40±4.27, önkoşullama olmaksızın sadece iskemi ve reperfüzyon yapılan grupta %65±4.11, kontrol grubunda %2±0.66 bulundu. Önkoşullama yapılan grupta, yapılmayan gruba göre apoptotik hücre sayısı anlamlı derecede azdı (p

The effect of ischemic preconditioning on myocardial apoptosis: a rat ischemia-reperfusi model

Background: One of the approaches developed to prevent or reduce ischemic cell damage is ischemic preconditioning. In this rat model, we investigated the effect of ischemic preconditioning on myocardial apoptosis. Methods: Thirty male Wistar rats were used. Following a left thoracotomy, the heart was exposed and isolated in all the rats. Ten control rats remained untreated. In 10 rats (ischemia group), the left main coronary artery was occluded for 30 min and reperfused for 120 min. The remaining 10 rats (preconditioning group) underwent 5 min of occlusion and 5 min of reperfusion before 30 min occlusion and 120 min reperfusion. At the end of the experiments, the hearts were removed and assayed for immunohistochemical staining for bcl-2 expression.Results: By immunohistochemical staining for bcl-2, the percentage of apoptotic cells was found as 40±4.27% in the preconditioning group, 65±4.11% in the ischemia group without preconditioning, and 2±0.66% in the control group. Compared to the ischemia group, the number of apoptotic cells was significantly lower in the preconditioning group (p

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