ARGININE-SUPPLEMENTED DIETS INHIBIT ENDOTOXIN-INDUCED BACTERIAL TRANSLOCATION IN MICE

We studied the effects of supplemental dietary arginine (ARG) on endot oxin-induced bacterial translocation. Mice were fed a 20%-casein diet (control) or a 20%-casein diet supplemented with 2% or 4% ARG and then injected with lipopolysaccharide (1 mg/500 mu l). The incidence of ba cterial translocation was noted by the recovery of viable organisms fr om the mesenteric lymph node (MLN) and spleen. The mortality rates of the mice were 40%, 10%, and 20% in the control group and 2%- and 4%-AR G groups, respectively. Of the surviving mice, bacterial translocation occurred in 100% of the control group, in 56% (MLN) and 56% (spleen) in the 2%-ARG group, and in 36% (MLN) and 25% (spleen) in the 4%-ARG g roup. Quantitative colony counts and median numbers of viable bacteria were lower (p < 0.05) in the 2%-ARG group and slightly lower in the 4 %-ARG group compared with the control group. MLN and spleen weights ex pressed as a percentage of body weight were heavier (p < 0.05) only in the 2%-ARG group. These results support the concept that bacteria may translocate from the gut to other organs and be a potential source of lethal infection after injury, and that supplementation with 2% or 4% ARG could improve outcome.