The Possible Protective Role of Vitamin C against Toxicity Induced by Lead Acetate in Liver and Spleen of Adult Albino Rats (Light and Electron Microscopic Study)

摘要

Background: lead toxicity has been recognized as a major environmental health hazard worldwide affecting both humans and animals at all ages especially young children in humans. Lead does not have any beneficial biological effects to humans and its presence at high concentrations produce very undesirable toxic consequences to humans affecting all the body organs. Ascorbic acid is probably the most widely studied vitamin when it helps to prevent lead induced oxidative stress. Its property of quenching ROS along with metal chelation makes it a potential detoxifying agent for lead. Aim of work : this study aimed to detect the possible protective effect of vitamin C against toxicity induced by lead acetate in liver and spleen of adult albino rats by light and electron microscope. Material and Methods: 40 adult male albino rats were used in this work. They were categorized into four groups each group was consisted of ten rats as follows: group I (Control group): The rats received 1ml 0.9% sodium chloride orally every day for 28 days. Group II: rats received vitamin C in a dose of 27 mg/day orally every day for 28 days. Group III: rats received lead acetate in a dose of 10.8 mg/kg; orally every day for 28 days. C group IV: rats received vitamin C in a dose of 27 mg of one hour prior to administration of 10.8 mg/kg of lead acetate orally every day for 28 days. Finally, on the 29th day, the rats were anesthetized with ether and their abdomens were opened and their livers and spleens were excised and divided to small slices and prepared for light and electron microscopic examination. Results: results of the present study revealed that administration lead acetate to rats produced harmful effects on the rat's liver and spleen; showed distortion of liver architecture with marked vacuolar degeneration of the swollen hepatocytes with cytoplasmic vaculations and condensed pyknotic nuclei. Central vein was dilated and congested, some of blood sinusoids were obliterated and others showed congestion and hemorrhage. Portal tract also showed congestion of the portal vein with mononuclear cellular infiltration in the portal tract area. Collagen deposition was detected around the central vein, between the cords of hepatocytes and in the blood sinusoids. Portal tracts expanded by thick collagen fibers also. And spleen showed distorted splenic architecture with massive hemorrhagic areas in the red pulps and highly reduced white pulps (diffusion of white pulp into the red pulp) and marked degeneration in the lymphocytes with necrotic foci with marked collagen deposition around the splenic arterioles and in the red pulps. and these effects relatively improved by administration of vitamin C. Sections were examined by light microscopic examination. Conclusion: lead acetate caused histological changes in liver and spleen of adult albino rats most probably through oxidative stress. Vitamin C therapy could ameliorate these changes in liver and spleen and this may be attributed to its antioxidant and free radicals scavenging properties. This may indicate the effectiveness of vitamin C in prevention of lead acetate toxicity on liver and spleen.