Abstract:

OBJECTIVE: To study the effects of 2, 4-dichlorophenoxyacetic acid (2, 4-D) on early neuro-behavior development and oxidative stress in offsprings. METHODS:Pregnant Wistar rats were treated with 2, 4-D by gavage, in doses of 0, 25, 50, 100 mg/kg once a day from gestation day 2 until postnatal day 21. Then the early physiological and neurobehavioral indexes in the offsprings were measured. The levels of MDA, GSH and the GSH-Px activities in brain tissues of newborn rat were determined. RESULTS:The weights of offspring in the 100 mg/kg 2, 4-D group were lower than in control after postnatal day 14(P<0.05) and the weights of offspring in the 50 mg/kg 2, 4-D were lower than in control after postnatal day 21(P<0.05). The physiologic markers including eye opening, pinna detachment, hair growth, tooth growth etc in all treated groups were not affected in contrast to the control group, cliff avoidance, mid-air righting and acoustic startle in the 100 mg/kg 2, 4-D group were delayed(P<0.05). The level of GSH and GSH-Px activities decreased in the 100 mg/kg 2, 4-D group, while the level of MDA was elevated in the 50 and 100 mg/kg 2, 4-D groups. CONCLUSION:Early neurobehavioral development of offspring rats could be impaired by 2, 4-D due to its disturbance to the homeostasis of oxidation and anti-oxidation system.

Key words: 2, 4-dichlorophenoxyacetic acid, neurobehavior, malondialdehyde, glutathione, glutathion peroxidase