Bahar AKKAYA, Nursel ŞAHİN, Hanife Karakaya KABUKÇU, Tülin Aydoğdu TİTİZ, Mehmet KABUKÇU, Cengiz TÜRKAY, Rabin SABA, Ömer ÖZBUDAK

The association between the development of renal artery atherosclerosis and chronic Pseudomonas aeruginosa infection in rats

Amaç: Bu çalışmada Psödomonas aeruginosa (P. aeruginosa) ile sıçan modelinde oluşturulan kronik akciğer infeksiyonlarının renal arterde ateroskleroz oluşumundaki rolü araştırıldı.Çalışma planı: Altmış altı Wistar albino sıçan her grupta 14 ile 20 adet olacak şekilde randomize olarak dört gruba ayrıldı. Grup 1 (n=20) ve grup 3 (n=16) %1 kolesterol eklenmiş diyet ile, grup 2 (n=14) ve grup 4 (Kontrol grubu) standart sıçan yemi ile beslendi. Sıçanların trakeaları anestezi altında cerrahi olarak çıkarıldı. Çalışma periyodu esnasında dört haftalık aralıklarla toplam beş defa bir enjektörle grup 1 ve 2'ye P. aeruginosa süspansiyonu ile grup 3 ve 4'e ise serum fizyolojik ile intratrakeal inokülasyon yapıldı. Kolesterol seviyeleri anestezi altında kuyruktan alınan kan örneklerinden değerlendirildi.Bulgular: Histopatolojik incelemelerde en fazla luminal incelme olan segment gözle inceleme yoluyla seçildi ve her segmentten 8-10 kesit hazırlanarak Olympus CH 40 mikroskop ile incelendi. Örneklerin medial ve neointimal bölgeleri bilgisayarlı görüntü analizi ile analiz edildi.Sonuç: Kesitler incelendiğinde kontrol grubundaki sıçanların esas olarak normal renal arter duvarı yapısına sahip olduğu görüldü. İnfekte edilen ve %1 kolesterol eklenmiş diyet ile beslenen grupta renal arterlerde tipik preaterosklerotik değişiklikler gelişti. Bu çalışmada bir sıçan modelinde P. aeruginosa ile oluşturulan kronik akciğer infeksiyonu ve yüksek kolesterol ile beslenmenin renal arter intima-media kalınlığını artırdığı ilk defa olarak gösterildi. Bu bulgular kronik infeksiyonun uzak etkilerinin ateroskleroz oluşumunda bir etyolojik faktör olduğunu güçlü şekilde düşündürmektedir.

Sıçanlarda renal arterde ateroskleroz gelişimiyle kronik Psödomonas aeruginosa infeksiyonu arasındaki ilişki

Background: In this study we investigated the role of chronic lung infections induced by Pseudomonas aeruginosa (P. aeruginosa) in a rat model in the development of renal artery atherosclerosis.Methods: Sixty-six Wistar albino rats were randomly divided into four groups each consisting of 14 to 20 rats. The rats in group 1 (n=20) and group 3 (n=16) were fed with a 1% cholesterol supplemented diet, whereas the rats in group 2 (n=14) and group 4 (Control group) were fed with regular rat chow. Rats' tracheas were surgically explored under anesthesia. Intratracheal inoculation was performed with P. aeruginosa suspension in group 1 and 2 or 0.1 ml saline in groups 3 and 4 via a syringe five times with four-week-intervals during the study period. Cholesterol levels were measured in blood samples collected from the tail under anesthesia.Results: In histopathological examinations; the segment with greatest luminal narrowing was selected by visual inspection and 8-10 slides prepared from each segment were examined under Olympus CH 40 microscope. Medial and the neointimal areas of the specimens were analyzed by computed image analysis.Conclusion: The rats in the control group exhibited mainly normal renal artery wall structure on cross sections. The rats that were infected and fed with 1% cholesterol diet developed typical preatherosclerotic changes in the renal arteries. In this study, it was demonstrated for the first time that both chronic lung infection with P. aeruginosa and high cholesterol f eeding a ccelerated the increases of the renal artery intima-media thickness in a rat model. These findings strongly suggest that the distant effects of chronic infection are an etiological factor in genesis of atherosclerosis.

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