[Mutagenicity test of antithyroid agent, methimazole--dominant lethal mutation test on male mice (author's transl)]

Mutagenicity test of Methimazole (MMI) was performed by means of dominant lethal mutation test in the male mice. Male mice were treated with a single s.c. injection of 45 mg/kg or 90 mg/kg MMI. Mean body weights were slightly decreased and mating rates were low immediately after treatment of MMI. Mean numbers of living implants at any periods examination up to 6 weeks after the treatment were compared with Salin Control, indicating lack of dominant lethality of MMI. On the other hand, EMS and MMC known mutagens and reference agents used in the present study, induced dominant lethalities at a single s.c. injection respectively.