Intestinal blood flow alterations in postoperative intraabdominal adhesion formation and the role of Endothelin-1 blockade

BACKGROUND: The current study was planned to investigate intestinal blood flow alterations and the role of ET-1 receptor blockade in the formation of postoperative intraperitoneal adhesion formation.
METHODS: Twenty-eight adult Wistar Albino rats weighing between 250 g and 300 g were divided into four groups. Control group (group 1; n=7) did not undergo any operation. Sham group (group 2; n=7) had only laparotomy. In the adhesion group (group 3; n=7), peritoneal patch (1x1 cm) excision from the right abdominal wall and cecal abrasion were done as "adhesion model operation". One week following this, treatment group (group 4; n=7) received a non-selective ET-1 receptor blocking agent bosentan (30 mg/kg, IP) intra-abdominally, once a day for four days. Intestinal blood flow through the superior mesenteric artery was measured, on postoperative seventh day. Adhesion severity and extension as well as myeloperoxidase activity in the adhesion were calculated.
RESULTS: Mean intestinal blood flow significantly increased in adhesion group (81.9±5.6 ml/100 g) when compared to group 1 (65.5±1.2 ml/100 g). Bosentan caused a significant decrease (44.3±6.9 ml/100 g) in intestinal blood flow when compared to group 1 and group 2. Sham group (62.2±1 ml/100 g) had similar blood flow level with the control group (65.5±1.2 ml/100g). Adhesion scores were similar in adhesion and Bosentan groups. Sham group had almost no adhesions. Myeloperoxidase activity in adhesion tissue was significantly higher in bosentan group.
CONCLUSION: Non-selective ET-1 receptor blockade has no effect on prevention of the formation of intra-abdominal adhesion, but causes a decrease in intestinal blood flow. Adhesion formation increases intestinal blood flow. Adhesion formation is accompanied by increased polymorphonuclear infiltration despite bosentan treatment.

Ameliyat sonrasý karýn içi yapýþýklýk oluþumunda baðýrsak kan akýmýndaki deðiþiklikler ve Endotelin-1 bloðunun rolü

AMAÇ: Ameliyat sonrasý periton içi yapýþýklýk oluþumunda baðýrsak kan akýmý deðiþikliklerini incelemek ve Endotelin-1 (ET-1) reseptör blokajýnýn rolünü araþtýrmaktýr.
GEREÇ-YÖNTEM: Çalýþmada 250-300 gr aðýrlýðýnda 28 adet Wistar-Albino eriþkin sýçan eþit olarak dört gruba ayrýldý. Kontrol grubuna (grup 1; n=7) ameliyat uygulanmadý. Sham grubuna (grup 2; n=7) sadece laparotomi yapýldý. Yapýþýklýk grubuna (grup 3; n=7) sað karýn duvarýndan 1x1 cm’lik peritoneal yama eksizyonu ve çekal abrazyon, “yapýþýklýk model ameliyatý” olarak uygulandý. Tedavi grubuna (grup 4; n=7); bir non-selektif ET-1 reseptör blokeri olan bosentan (30 mg/kg, IP) periton içi yoldan dört gün süreyle günde bir kez verildi. Ameliyat sonrasý yedinci gün, superior mezenterik arterin beslediði baðýrsak kan akýmý ölçüldü. Yapýþýklýk þiddeti ve yaygýnlýðý ile yapýþýklýktaki miyeloperoksidaz (MPO) aktivitesi ölçüldü.
BULGULAR: Ortalama baðýrsak kan akýmý grup 1 (65.5±1.2 ml/100 gr) ile kýyaslandýðýnda yapýþýklýk grubunda (81.9±5.6 ml/100 gr) belirgin olarak artmýþtý. Grup 1 ve grup 2 ile karþýlaþtýrýldýðýnda bosentanýn (44.3±6.9 ml/100 gr) baðýrsak kan akýmýnda belirgin azalmaya neden olduðu görüldü. Sham grubunun (62.2±1 ml/100 gr) kan akým seviyeleri kontrol grubundakilerle (65.5±1.2 ml/100 gr) benzerlik gösterdi. Yapýþýklýk skorlarý, yapýþýklýk ve bosentan gruplarýnda benzer bulundu. Sham grubunda neredeyse hiç yapýþýklýk görülmedi. Bosentan grubunda yapýþýklýk dokusu MPO aktivitesi belirgin olarak artmýþtý.
SONUÇ: Non-selektif ET-1 reseptör blokajýnýn periton içi yapýþýklýk oluþumunun önlenmesinde bir etkisi yoktur ancak, baðýrsak kan akýmýnda azalmaya neden olur. Yapýþýklýk oluþumu baðýrsak kan akýmýný arttýrýr. Yapýþýklýk oluþumu, bosentan tedavisine raðmen artmýþ polimorfonükleer (PMN) infiltrasyonu ile birliktedir.