Studies of the route, magnitude, and time course of bacterial translocation in a model of systemic inflammation
M. R. Mainous, P. Tso, R. D. Berg and E. A. Deitch
Department of Surgery, Louisiana State University Medical Center, Shreveport, La.
Bacteria have been documented to translocate from the gut to systemic
organs, yet the exact route by which they translocate remains unclear. To
determine the route of bacterial translocation, different dosages of
zymosan were used to activate complement and cause systemic inflammation.
At a zymosan dose of 0.1 mg/g, bacteria translocated only to the mesenteric
lymph node complex, whereas at a dose of 0.5 mg/g the bacteria translocated
systematically. In rats receiving 0.5-mg/g doses of zymosan, the bacteria
appeared to reach systemic organs via the portal blood rather than via the
mesenteric lymph, as bacteria were present in 87% of portal blood samples
but only 25% of lymph samples. The number of bacteria exiting the portal
vein was 11,500 times greater than the number exiting via the lymph. Thus,
both the route and extent of bacterial translocation varies based on the
magnitude of the inflammatory insult, with the portal blood being the major
route of bacterial translocation to systemic organs.
