Ulus Travma Acil Cerrahi Derg. 2011; 17(2): 97-102 | DOI: 10.5505/tjtes.2011.98958

Evaluation of the effects of losartan on a random pattern skin flap model in rats

Cemile Nurdan Öztürk¹, Erdem Tezel¹, Özben Yalçýn^2
1Department Of Plastic Reconstructive And Aesthetic Surgery, Marmara University, Faculty Of Medicine, Ýstanbul, Turkey
²Department Of Pathology, Marmara University, Faculty Of Medicine, Ýstanbul, Turkey

BACKGROUND: Losartan, a drug with antiinflammatory properties, has been shown to prevent ischemic injury in various organs. The purpose of the present study was to investigate the effects of losartan on ischemic skin flaps and on flap survival.
METHODS: A 3x9 cm dorsal flap was elevated in 24 Sprague-Dawley rats. Rats received the following treatment for seven days: Group I (n=8): 10 mg/kg losartan; Group II (n=8): 40 mg/kg losartan; and Group III (n=8): nonionized water. At the end of the seventh day, the viable flap areas were calculated, and histological analysis was conducted to count cells and capillaries in microscopic fields.
RESULTS: Mean flap survival was 61%, 56% and 60% in Groups I, II and III, respectively. Comparison of flap survival between groups did not yield any significant difference (p>0.05). Ischemic zones of the flaps in all groups demonstrated an increase in number of neutrophils, fibroblasts and capillaries (p<0.05), whereas no difference was seen in mast cells. The cell counts in the viable areas of the flaps showed a significant
decrease in fibroblasts in the group treated with 40 mg/kg losartan (p<0.05). The number of neutrophils, mast cells and capillaries was not influenced by treatment.
CONCLUSION: Losartan does not improve skin flap survival but it has a significant
antiproliferative effect on fibroblasts.

Keywords: Angiotensin, AT1; fibroblast; flap survival; ischemic flap; ischemia- reperfusion; losartan; reperfusion injury

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Sýçan sýrt deri flebinde losartanýn etkisinin deðerlendirilmesi

Cemile Nurdan Öztürk¹, Erdem Tezel¹, Özben Yalçýn^2
1Marmara Üniversitesi Týp Fakültesi, Plastik Rekonstrüktif Ve Estetik Cerrahi Anabilim Dalý, Ýstanbul
²Marmara Üniversitesi Týp Fakültesi, Patoloji Anabilim Dalý, Ýstanbul

AMAÇ: Losartanýn enflamasyonu baskýlayarak çeþitli organlarda iskemi-reperfüzyon hasarýný azalttýðý ve enfarkt alanýný küçülttüðü ortaya konmuþtur. Bu çalýþma, losartanýn deri fleplerindeki iskemik bölgeye ve flep sürvisine etkisini ortaya koymak amacýyla planlandý.
GEREÇ VE YÖNTEM: Sprague-Dawley sýçanlarda (n=24) 3x9 cm boyutlarýnda kaudal
pediküllü sýrt flebi kaldýrýldý. Sýçanlar 3 gruba ayrýlarak 1. gruba 10 mg/kg, 2. gruba 40 mg/kg losartan ve 3. gruba distile su verildi. Yedi günlük tedavinin sonunda fleplerdeki
canlý doku alaný hesaplanarak gruplar arasýnda karþýlaþtýrýldý. Ek olarak fleplerin proksimal ve iskemik bölgelerinde nötrofiller, fibroblastlar, mast hücreleri ve kapillerler sayýldý.
BULGULAR: Fleplerdeki canlý doku alanlarý ortalamasý 1., 2. ve 3. gruplarda sýrasýyla %61, %56 ve %60 olarak hesaplandý. Gruplar flep saðkalýmý açýsýndan arþýlaþtýrýldýðýnda anlamlý fark bulunmadý (p>0,05). Tüm gruplarda fleplerin iskemik bölgesinde nötrofil, fibroblast ve kapillerlerde anlamlý artýþ saptanýrken (p<0,05), mast hücre sayýsýnda fark bulunmadý. 40 mg/kg losartan ile tedavi alan grupta fleplerin yaþayan bölgesinde fibroblast sayýsý anlamlý olarak azaldý (p<0,05). Nötrofil, mast hücreleri ve kapiller sayýlarý ise tedaviden etkilenmedi.
SONUÇ: Losartan sýçan sýrt deri flebinin sürvisini arttýrmamakta ancak fibroblastlar üzerine anlamlý antiproliferatif etkisi bulunmaktadýr.

Anahtar Kelimeler: Anjiyotensin, AT1; flep sürvisi, fibroblast; iskemik flep; iskemi reperfüzyon; losartan; reperfüzyon hasarý

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