Abstract
In order to investigate the mode of the delayed toxicity of streptothricin antibiotics, 14C-glycyl-racemomycin-A and racemomycin-D were each administered intravenously to mice and rats in a seuviving dose. As to the distribution of 14C-glycyl-racemomycin-A in the organs of mice, studies confirmed us that it was distributed in kidney in a high concentration in comparison with the distribution in the other organs. Therefore, pathohistological reviews were carried out on the kidney which was whitened macroscopically. As a result, severe toxicity wide-spread in the cortex renis was observed in the kidney. From these results, it was recogenized that streptothricin antibiotics produce nephrotoxicity. As to the developmental mechanism of the delayed toxicity, the authors presented the assumption that after the administered antibiotic us, in vivo, transformed into acid, lactam ring of which is broken from examination of radiochromatogram of metabolite in urine, and that the acute toxicity of that acid is responsible for the delayed toxicity.
