COMPARISON OF POPLITEAL LYMPH-NODE RESPONSES IN VARIOUS STRAINS OF RATS

Outbred (namely Wistar and Sprague-Dawley) and inbred (Wistar-Furth, L ewis, Fisher 344 and Brown-Norway) strains of rats were screened for t heir responses to reference compounds in the popliteal lymph node (PLN ) assay, Streptozotocin and diphenylhydantoin gave positive responses as evidenced by increased weight and cellularity indices in all strain s used whereas procainamide, isoniazid and barbital consistently gave negative responses. Although these findings overall are in agreement w ith previous investigations involving these compounds, the lack of mar ked interstrain differences in PLN responses argues against a strong i mmunogenetically controlled mechanism as could be assumed in presumabl y auto-immune reactions. The question is raised whether drug-induced s ide-effects predicted by the PLN assay are basically non-autoimmune as suggested by clinical and immunological findings in man.