BACKGROUND: Leucocyte recruitment is a key feature in ischaemia-reperfusion (I/R)-triggered tissue injury. However, the mechanisms underlying leucocyte-endothelium interactions in the large bowel remain elusive because of a previous lack of models to examine the colonic microcirculation. The aim of this study was to develop and validate a novel method for studying reperfusion-induced leucocyte-endothelium interactions in the colon. METHODS: The superior mesenteric artery was occluded for 30 min in male C57/Bl6 mice and leucocyte responses were analysed in colonic venules after 30-240 min of reperfusion. Analysis of leucocyte rolling and adhesion in colonic venules was made possible by an inverted approach using intravital fluorescence microscopy. RESULTS: Thirty minutes of ischaemia and 120 min of reperfusion induced the strongest and most reproducible increase in leucocyte rolling and adhesion. This was associated with a significant increase in colonic levels of malondialdehyde (MDA). Administration of allopurinol and superoxide dismutase reduced I/R-induced leucocyte responses in a dose-dependent manner. Pretreatment with allopurinol attenuated the tissue content MDA in the colon by more than 60 per cent. CONCLUSION: A new method for examining I/R-induced leucocyte responses in the colonic microcirculation is described. Oxygen free radicals play an important role in triggering leucocyte rolling and adhesion in colonic venules.
BACKGROUND: Leucocyte recruitment is a key feature in ischaemia-reperfusion (I/R)-triggered tissue injury. However, the mechanisms underlying leucocyte-endothelium interactions in the large bowel remain elusive because of a previous lack of models to examine the colonic microcirculation. The aim of this study was to develop and validate a novel method for studying reperfusion-induced leucocyte-endothelium interactions in the colon. METHODS: The superior mesenteric artery was occluded for 30 min in male C57/Bl6 mice and leucocyte responses were analysed in colonic venules after 30-240 min of reperfusion. Analysis of leucocyte rolling and adhesion in colonic venules was made possible by an inverted approach using intravital fluorescence microscopy. RESULTS: Thirty minutes of ischaemia and 120 min of reperfusion induced the strongest and most reproducible increase in leucocyte rolling and adhesion. This was associated with a significant increase in colonic levels of malondialdehyde (MDA). Administration of allopurinol and superoxide dismutase reduced I/R-induced leucocyte responses in a dose-dependent manner. Pretreatment with allopurinol attenuated the tissue content MDA in the colon by more than 60 per cent. CONCLUSION: A new method for examining I/R-induced leucocyte responses in the colonic microcirculation is described. Oxygen free radicals play an important role in triggering leucocyte rolling and adhesion in colonic venules.
Authors: Stefan Santen; Yusheng Wang; Matthias W Laschke; Michael D Menger; Bengt Jeppsson; Henrik Thorlacius Journal: Int J Colorectal Dis Date: 2010-07-01 Impact factor: 2.571
Authors: Sophie Gibbings; Nancy D Elkins; Hillary Fitzgerald; Janice Tiao; Mari E Weyman; Gayle Shibao; Mehdi A Fini; Richard M Wright Journal: J Biol Chem Date: 2010-11-08 Impact factor: 5.157
Authors: Amjid Ali Riaz; Ming Xiu Wan; Thilo Schaefer; Rene Schramm; Henrik Ekberg; Michael D Menger; Bengt Jeppsson; Henrik Thorlacius Journal: Ann Surg Date: 2002-12 Impact factor: 12.969
Authors: Stefan Dold; Matthias W Laschke; Yilin Zhau; Martin Schilling; Michael D Menger; Bengt Jeppsson; Henrik Thorlacius Journal: Inflamm Res Date: 2009-10-15 Impact factor: 4.575