Abstract
The study evaluated the haematological and some antioxidant enzymes response to lead toxicity in male Wistar rats. Twenty male Wistar rats were divided into four groups viz., A, B, C and D. Group A served as the control while groups B, C and D were treated with 200, 300 and 400 ppm of lead (Pb) as lead acetate, respectively. Doses were orally administered in divided doses by intubation to ensure that each rat had the specified doses, after which they have access to water and feed. At the end of two weeks of treatment, blood samples were collected via the median canthus into heparinised tubes for blood lead determination and haematological analysis after which the remaining blood was centrifuged to obtain the plasma for determination of malonydialdehyde, catalase, superoxide dismutase and peroxidase levels. There was a significant increase in blood lead concentrations ranging from 2.15±0.10 µg/dl to 9.21±0.05 µg/dl which was dose dependent while decreases in packed cell volume and the red blood cell counts ranging from 32-53% and 15-52%,respectively. At the highest dose of 400 ppm of lead there was significant decrease in the neutrophils and lymphocytes. There was significant (P<0.05) dose dependent increases in malondialdehyde while the activities of catalase, peroxidase and superoxide dismutase were significantly (P<0.05) reduced. In conclusion, lead disrupts the haematological system leading to generation of free radicals that overwhelm the antioxidant enzymes thus leading to oxidative stress.