The effect of isoniazid (INH) on Chinese hamster and mouse spermatogonia

Acute and chronic treatment of Chinese hamsters and mice with 5, 25 and 125 mg/kg isoniazid (INH) given by oral intubation did not enhance the chromosomal aberration frequencies in spermatogonia. The structural and numerical aberration rates remained in the range of spontaneous events even after the chronic treatment over 12 weeks with 3 x 125 mg/kg INH per week. This dose is much higher than normally used for prevention and therapy in man (3--16 mg/kg).