Effects of prenatal AZT on mouse neurobehavioral development and passive avoidance learning

Recent evidence has shown that perinatal administration of zidovudine (AZT) to HIV-infected mothers reduces the risk of maternal-infant transmission o f the virus. Treatment of pregnant seropositive women with AZT is becoming a common medical practice, despite the paucity of information about the pot ential neurotoxic/behavioral-teratogenic effects of AZT on the developing o rganism. The aim of the present study is to evaluate in mice the short-, me dium-, and long-term effects of prenatal exposure to AZT on neurobehavioral development. Pregnant mice were given 0.2, 0.4, and 2.0 mg/ml AZT in drink ing water from day 10 of gestation to delivery. Offspring's viability was s everely affected in the 2.0 mg/ml AZT group. Thus, behavioral analysis was carried out in offspring of 0.2 and 0.4 mg/ml AZT treated females only. Som e limited but significant alterations were found, such as stunted body weig ht, delayed appearance of the pole-grasping reflex, and a slight impairment in the acquisition phase of a passive avoidance response. Moreover, sexual differences in some items of the social behavior repertoire appeared to be affected by AZT treatment. (C) 1999 Elsevier Science Inc. All rights reser ved.