Abstract

This study was designed to investigate the interactive roles of terpenoid extract from the leaves of Neem plant (Azadirachta indica, A. Juss) on lead-induced toxicity in pregnant rabbits and the resulting litters. Terpenoid was extracted from the air dried leaves of A. indica by previously reported procedure. Pregnant rabbits (does) weighing between 1.8 - 2.0 kg was randomly divided into 4 treatment groups: Group I (Control Group) received olive oil (2 ml/kg body weight per day). Group II (Lead Group) received Lead acetate solution (50 mg/kg body weight per day). Group III (Positive Control Group) received ascorbic acid (400 mg/kg body weight per day) and Group IV (Terpenoid Group) received with terpenoid extract (300 mg/kg body weight per day). Lead acetate solution (50 mg/kg body weight per day) was later administered to animals in groups III and IV. The animals were treated for 11 days starting from day 14 of gestation period of the animals. The does and the litters (young rabbits) were sacrificed 4 weeks after parturition. Blood plasma, whole blood was obtained for biochemical and lead analysis respectively. The liver, kidney, heart and lungs were removed for lead analysis. Lead concentration in the blood and the tissues was determined by atomic absorption spectroscopy (AAS). The total protein concentration in the plasma and liver homogenates were determined using biuret reaction method. The plasma albumin concentration, hepatic marker enzymes, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities were also determined by standard spectrophotometric methods. The results revealed that, the terpenoid extract was able to reduce lead concentration in the blood, liver and kidney of pregnant rabbits. The levels of reduction was found to be statistically significant (p < 0.05) but the extract had no significant effect on its concentration of lead in the tissues of the litters, suggesting that the extract could not prevent inter placenta transfer of lead. Liver protein, plasma protein and albumin concentration, ALT and AST activities were not significantly different in all the groups. Conclusively, the extract was also able to reduce the lead burden in pregnant rabbits but could not produce the same effects on the litters.

Key words: Pregnant rabbit, lead, toxicity, terpenoid, blood.