STUDIES OF MICROBIAL POPULATIONS ARTIFICIALLY LOCALIZED IN VIVO. II. DIFFERENCE IN ANTITYPHOIDAL ACTIVITIES OF CHLORAMPHENICOL AND CHLORTETRACYCLINE 1

Abstract

A method is descr. for localizing bacterial populations in the peritoneal cavity of an animal for limited periods, to permit quantitative observations of certain biol. phenomena pertaining to the drug-host-parasite relationships of pathogenic bacteria and antimicrobial compounds. The bacteria are confined in the completely encased central layer of a triple-layered agar disc constructed of un-enriched, transparent, 3% agar. Since bacterial growth depends on diffusion into the agar of nutrient from the extracellular fluid of the host, the organisms exist in a state more closely approximating true parasitism than is possible in vitro. The agar in the peritoneal cavity was readily penetrated by penicillin, streptomycin, chlortetracycline, and chloramphenicol after parenteral or oral admn., and it was possible to correlate directly bacterial growth in the animal host with concns. of these drugs in the blood and body fluids.