Abstract

The toxic effect of lead (Pb) on the haematology and DNA of rats has been reported to result in alteration in blood cell counts and mutations that may cause cancers. In this study, the ameliorative effect of the methanol extract of Azadirachta indica leaf (MEAI) on lead induced haematological dyscrasias and micronuclei formation was studied on male Wistar rats. Rats of average weight 100g to 150g, were randomly divided into 7 groups of 10 rats each. Group A rats served as the control group while groups B-D rats were exposed to 0.1% lead acetate and groups E-G rats exposed to 0.2% lead acetate. Groups C and F rats were treated with 100mg/kg MEAI while groups D and G rats were treated with 200mg/kg MEAI. Standard assays were employed in the assessment of haematological changes while the micronuclei in vivo assay technique was used to test for genotoxicity. There was a significant (p<0.05) decrease in PCV and haemoglobin levels, while there was a significant (p<0.05) increase in monocyte counts in group B compared to the control animals (group A). These parameters were significantly (p<0.05) reversed at treatment with 100 (group C) and 200mg/ml (group D) MEAI. There was also significant (p<0.05) and dose dependent reduction in the frequency of micronucleated polychromatic erythrocytes (MNPCEs) observed in the MEAI treated groups (Groups C, D, E and F) compared to the lead induced groups (Groups B & E). This study demonstrates MEAI as a potential drug candidate in the amelioration of lead acetate induced haematological dyscrasias amd genotoxicity.