Paradoxical attenuation of leukocyte rolling in response to ischemia- reperfusion and extracorporeal blood circulation in inflamed tissue

• Published in: American journal of physiology. Heart and circulatory physiology 2005-07, Vol.289 (1), p.H330-H335
• Main Authors: Schafer, Stephan C, Sehrt, Desiree N, Kamler, Markus, Jakob, Heinz, Lehr, Hans-Anton
• Format: Article
• Language: English
• Subjects: Animals; Cricetinae; Extracorporeal Circulation; Leukocyte Rolling - drug effects; Leukotriene B4 - pharmacology; Mesocricetus; Microscopy, Fluorescence; Muscle, Skeletal - blood supply; Myositis - physiopathology; Reperfusion Injury - physiopathology; Venules - physiopathology
• ISSN: 0363-6135; 1522-1539
• DOI: 10.1152/ajpheart.00674.2004

1 Institute of Pathology, University of Mainz Medical Center, Mainz; and 2 Clinic for Thorax and Cardiovascular Surgery, University Clinic of Essen Medical Center, Essen, Germany Submitted 7 July 2004 ; accepted in final form 24 January 2005 In contrast to acute preparations such as the exteriorized mesentery or the cremaster muscle, chronically instrumented chamber models allow one to study the microcirculation under "physiological" conditions, i.e., in the absence of trauma-induced leukocyte rolling along the venular endothelium. To underscore the importance of studying the naive microcirculation, we implanted titanium dorsal skinfold chambers in hamsters and used intravital fluorescence microscopy to study venular leukocyte rolling in response to ischemia-reperfusion injury or extracorporeal blood circulation. The experiments were performed in chambers that fulfilled all well-established criteria for a physiological microcirculation as well as in chambers that showed various extents of leukocyte rolling due to trauma, hemorrhage, or inflammation. In ideal chambers with a physiological microcirculation (100 leukocytes/mm), we observed a paradoxical reduction of leukocyte rolling after ischemia-reperfusion injury or extracorporeal blood circulation. A similar effect was observed when we superfused leukotriene B 4 (LTB 4 ) onto the chamber tissue. The initial increase in leukocyte rolling in response to an LTB 4 challenge was reversed by a second superfusion 90 min later. These observations underscore 1 ) the benefit of studying leukocyte-endothelial cell interaction in chronically instrumented chamber models and 2 ) the necessity to strictly adhere to well-established criteria of a physiological microcirculation. leukotriene B 4 ; animal model; intravital microscopy Address for reprint requests and other correspondence: H.-A. Lehr, Institut Universitaire de Pathologie, Centre Hospitalier Universitaire Vaudois (CHUV), Rue du Bugnon 25, CH-1011 Lausanne, Switzerland (E-mail: Hans-Anton.Lehr{at}hospvd.ch )