Plastic foil technique attenuates inflammation in mesenteric intravital microscopy

Background Interpretation of intravital microscopic observations is complicated by the "inflammatory"-type response to the trauma inflicted on the tissue by the surgical preparation. The present study evaluates different experimental conditions for prolonged observations of the mesenteric microcirculation in the rat. Methods. The mesentery was exteriorized through a median laparotomy and subjected to an organ bath or a modified plastic foil technique. Hemodynamic, metabolic, respiratory, and microcirculatory data were analyzed. Results. In contrast to the plastic foil technique, which yielded stable baseline values over a 5-h observation period, venular velocity and wall shear rates decreased significantly in the organ bath technique, and leukocyte adhesion to the endothelium was significantly increased. Likewise, abdominal blood how decreased significantly by 35% and base excess declined (-10.0 +/- 0.4 mmol/L) in the organ bath, with reduced pCO(2) (26.4 +/- 2.5 mm Hg vs 33.7 +/- 1.1 mm Hg in plastic foil technique) due to respiratory pH compensation. Conclusions. The plastic foil technique was found clearly superior to the organ bath technique for maintenance of stable baseline metabolic, hemodynamic, and microcirculatory conditions in mesenteric intravital microscopy. (C) 2000 Academic Press.