OBJECTIVE: Being the major lymphoid organ of human body, spleen performs critical immunological functions such as bacteria depuration from bloodstream and precocious antibody production against various antigenic particles. Spleen, liver and lung accounts for more than 95% of phagocytic activity in humans. METHODS: We used intravenous inoculation of Escherichia coli AB1157 in Wistar rats in order to evaluate this function. Young and adult rats of both sexes were submitted to total splenectomy and compared to animals not submitted to any surgical procedure. Sixteen weeks later, rats of both groups were challenged with a suspension of E. coli labeled with Tc-99m, and, after twenty minutes, they were killed. Liver, lung, spleen and a blood clot sample were removed for radioactivity determination. The statistical study was performed with Student's t test. RESULTS: There were no significant differences in the radioactivity uptake obtained from young and adult splenectomized rats. However, these rats were associated with higher levels of blood counts than animals of the control group (p<0.0001) due to a larger bacteria remnant in the bloodstream. CONCLUSION: This finding suggests that some failure in mononuclear phagocytic system occurs in spleen absence adaptation, ratifying the necessity of development of alternative surgical techniques to total splenectomy in patients requiring spleen removal.
Spleen; Splenectomy; Technetium-99m; Escherichia coli; Phagocytosis
