Abstract
This paper reports a quantitative assessment of enhanced neutrophil adherence on venular endothelium which was induced by the infusion of a potent anaphilatoxin C 5 a and complement-activated serum. In vivo microscopy, equipped with a TV monitor and a videorecorder, was used to determine the numbers of rolling and adhering neutrophils in venules of exteriorized rat mesentery. Experiments run at the duration from the first one hour after exteriorization to following one hour when external disturbances induced by surgical procedures on hemodynamics and numbers of circulating neutrophils were minimized. The results showed; irrespective of infusion of C5a or activated serum, little difference in number of rolling neutrophils before and after infusion was observed, whereas the number of adhering neutrophils was significantly increased especially 10-30 min after infusion, followed by a gradual decrease. A dose-dependent increase was observed for C5a infusion. These resemble well leukostasis which was clinically observed during extracorporeal circulation using potent complement activation-inducing artificial dialyzers and artificial oxygenators. Enhanced adherence was discussed in conjunction with associative interactions between adhesive molecules expressed in both cell types.