Inhibition of ochratoxin A teratogenesis by zearalenone and diethylstilboestrol

The modifying effect of zearalenone (ZEN) and diethylstilboestrol (DES) on ochratoxin A (OCT A) teratogenesis was investigated in the mouse. The three compounds, either individually or in combination (OCT A + ZEN or OCT A + DES), were administered orally on day 9 of pregnancy and the offspring were examined on day 19. All of the foetuses surviving exposure to ZEN (5-20 mg/kg body weight) or DES (0.125 mg/kg) were morphologically normal, while a high percentage (31-40%) of those exposed to OCT A (1-2 mg/kg) exhibited gross abnormalities such as exencephaly, open eyelids and microphthalmia. These effects were either not seen or occurred in a relatively small percentage when the toxin was combined with ZEN or DES. The results indicate that these non-steroidal oestrogenic substances of mycological (ZEN) and synthetic (DES) origin may protect the foetus from the teratogenic effects of OCT A by some unknown mechanism.