Teratogenic and reproductive effects of ethanol in Long-Evans rats.

The effects of ethanol alone or ethanol and dieldrin given orally were investigated on the reproductive processes of female Long-Evans rots. Three studies were undertaken: effects on reproduction (phose 1), perinatal and postnatal effects {phase Ill}, and teratological effects (phose II}. Female Long-Evans rats were divided into five groups for all studies: group /-distilled water; group //-corn oil; group 111-4 mg Dieldrin/kg; group IV-500 mg aspirin/kg; and group V-0.4 ml ethanol/kg. For phase II, two additional groups were added to the experimental design: group Vl-4.0 ml ethanol/kg and group V/1-4 mg Dieldrin/kg and 0.4 ml ethanol/kg. In the phase I study, ethanol produced a significant increase in the number of malformed pups at birth: microphthalmia and paralysis were the defects noted. Aspirin caused significant teratogenic effects as well as maternal deaths from gastrointestinal hemorrhage. Dieldrin alone ccused no adverse effects. In the phase Ill study, except for maternal toxicity among aspirin-dosed dams, no adverse findings were elicited. In the phase II study, 0.4 ml ethanol/kg induced o significant increase in the frequency of soft tissue malformations such as microphthalr1ia and hydronephrosis. A 70-fold incre:;se in the ethanol dosage (4.0 ml/kg), caused embryolethality as well as soft tissue :erotology. Aspirin (500 mgfkg) caused skel£:al (cranial bone) defects and sofr tissue anomalies in pups; Dieldrin was withou; untoward effects. Dams given a combination of Dieldrin and 0.4 ml ethanol/kg displayed increased embryoletholity but no teratogenic effect was noted. These results suggest that the Long-Evans rat is a sensitive model for the induction of FAS at a dose level equivalent to one alcoholic drink per day in human females. The repartee· embryolethal effect of concommitont exposure to Dieldrin (on organochlorine pestici:ie} and ethanol deserves further evaluation.