PRENATAL EXPOSURE TO CYPERMETHRIN MODULATES RAT NK CELL CYTOTOXIC FUNCTIONS

The synthetic pyrethroid insecticide, cypermethrin, was given during g estation to pregnant rats by gavage in corn oil. Peripheral blood and spleen cytotoxic activity of dams and their offspring were then evalua ted at different times (30, 60, 90, 120 days) after birth. Pups showed a significant increase in peripheral blood natural killer (NK) and an tibody-dependent (ADCC) cytotoxic activity paralleled with a similar i ncrease in the percentage of NK-RP1(+) cells and decreased activity in the spleen. Pregnant cypermethrin-exposed dams showed no changes in p eripheral blood or spleen cytotoxic function during the postnatal peri od. Overall, these results suggest that immunomodulation of cytotoxic activity observed in the offspring is likely attributable to a specifi c effect of cypermethrin administered during the prenatal period. (C) 1997 Elsevier Science Ireland Ltd.