1984 年 37 巻 8 号 p. 1494-1506
Miocamycin (MOM) is a derivative of midecamycin, a macrolide antibiotic isolated from a culture broth of Streptomyces mycarofaciens1), 2). It is reported that MOM has the most interesting antibacterial properties among macrolide antibiotics3, 4) and is metabolized into 4 main metabolites of Mb1, Mb2, Mb6 and Mb125). It is also known that LD0 values of Mb1 were estimated more than 5,000 mg/kg without exhibiting any manifest toxic effects after single oral administration to male and female rats6).
The object of this study was to examine toxicological effects in male and female rats after repeated oral administration of Mb1, a metabolite of MOM, for 5 weeks at daily dosages of 125, 250, 500 and 1,000 mg/kg which were selected in consideration of the maximum tolerable dosage level of 1,000 mg/kg/day for MOM, non-crystalline solid, in the rat subacute toxicity studies as previously reported7).
