Effect of Age on Bacterial Translocation from the Gastrointestinal Tract in Mice

Abstract

To clarify the effects of age on bacterial translocation from the gastrointestinal tract, mice at the age of 1, 2, 4, 6, 12, and 15 months were antibiotic -decontam inated for 4 days and then inoculated orally with streptomycin-resistant Escheri chia coli C25. Mice treated with cyclophosphamide and untreated controls were tested for bacterial translocation to the mesenteric lymph nodes (MLN) 2 days later. The population levels of E. coli C25 in cyclophosphamide-treated and untreat ed mice were approximately 109' a and 109' S per gram of cecum, respectively, at each tested age. There were no significant differences in the incidence of transloca tion of E. coli C25 to MLN at any of the tested ages, whereas the number of E. coli C25 detected in MLN was higher in young mice than in aged mice in both the cyclophosphamide-treated and untreated groups. These findings suggest that bacterial translocation from the GI tract may be a more important problem in young animals than in aged animals.