Background: Low dose lead (Pb) exposure during pre- and postnatal periods implicates the development of CNS. Oxidative stress is considered to be a possible molecular mechanism involved in Pb neurotoxicity. In traditional herbal medicine, lemon balm (Melissa officinalis) is widely prescribed in restoration of memory disorders and CNS pathological states. Objectives: The goal of present study was to evaluate the potential protective property of Melissa with vitamin C (vit.C) during fetal and neonatal periods in lead acetate exposed Wistar rats. Material and methods: Forty virgin Wistar rats were mated and divided as follows; control, Pb, Pb+vit.C, Pb+25, 50 and 100 mg/kg BW Melissa. Treatments were started from 7th day of gestation and continued during lactation. Then the learning abilities and memory retrieving of four months old offspring were tested by Morris water and T mazes. Blood samples were collected from dams and serum Pb level was measured using atomic absorption technique. Results: Both Melissa and vit.C administrations decreased the serum Pb level in dams. Lead exposure dramatically reduced the learning ability and memory of offspring while vit.C and Melissa administration restored the learning scores to control level. However, there was no significant difference between control, Pb+Melissa and Pb+vit.C in learning scores. Conclusion: Melissa and vit.C significantly ameliorated the toxic effects of Pb and improved learning scores. Since there was no significant difference between animals treated with Melissa and vit.C, it can be concluded that similar to vit.C, Melissa has a potential protective and/or antioxidant effect in lead exposed rats.

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