Placental transfer of ochratoxin A and its cytotoxic effect on the mouse embryonic brain.

Pregnant ICR mice were given a single ip injection of 5 mg ochratoxin A/kg on day 11 or 13 of pregnancy. Concentrations of ochratoxin A in the maternal serum and tissues reached maximum levels within 2 hr of the injection and then decreased rapidly. The half-life of the toxin in serum was 28.7 hr on day 11 and 23.6 hr on day 13. On the other hand, the concentrations of ochratoxin A in the embryos were very low 2 hr after injection and then gradually increased up to 48 and 30 hr after injection on day 11 and 13, respectively. Pharmacokinetically, the embryo was found to be a 'deep' compartment. In mice treated with ochratoxin A on day 10 of pregnancy, the incidence of pyknotic cells in the telencephalon of the embryos began to increase 12 hr after injection to a peak between 36 and 48 hr, coinciding with the time of peak concentration of the toxin in the embryo.