Abstract

Introduction: Effects of stress on nervous system activity and development are well defined. In the present study, the effects of maternal stress on dopamine-related behavior in the offspring were studied. Methods: Female pregnant Wistar rats (200 g) were randomly exposed to the noise pollution stress (125 db) for 14 days (5 min/day). The time of exposure was random in order to avoid adaptation. The offspring were nursed by their mothers until the adolescence (200 g-3 mounts of age). These animals were examined for their seeking behavior including rearing, sniffing and locomotion using open field method. Twenty four hours later, they received subcutaneous administration of the dopamine D2 receptor antagonist, sulpiride (5 mg/kg) for evaluation of dopamine receptor sensitization. Results: Our results showed that sniffing was reduced (P<0.01), but both rearing (P<0.05) and locomotion (statically non significant) activity in the F2 of stress group was increased. Injection of sulpiride reduced animals activity (sniffing, rearing and locomotion) in both groups but the reduction was more pronounced in the stress group (P<0.001). Conclusion: It could be concluded that dopamine-related behavior differed in the experimental group, which was exposed to stress during intra-uterine life. In addition, the experimental group showed a pronounced response to sulpiride, which may be due to alteration in brain dopamine system activity in these animals.