Background: Increasing number of cardiovascular and digestive diseases in the world is�one of the problems threatening the public health. High cholesterol level, hyperlipidemy and oxidated lipoproteins are among the important risk factors. Liver, as the most important gland, affects the metabolism of these substances. Ascorbic acid, as a major antioxidant, inhibits lipoprotein oxidation. This study was conducted to evaluate the effects of ascorbic acid on serum lipoproteins and liver tissue in rabbits fed by high cholesterol diet.

Materials and Methods : This quasi-experimental research was conducted on 40 albino rabbits at the Faculty of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran. After adaptation to the new environments, rabbits were randomly divided into four equal groups: control group ascorbic acid group cholesterol group and ascorbic acid + cholesterol group. Blood samples were taken before and 40 days following the administration of the diet for serum lipids and lipoprotein analysis. After the completion of the study, the animals were anesthetized and the liver tissue was extracted on tissue processing. Serial tissue sectioning (thickness 5µ) were prepared for H&E staining and light microscopy studies. The Data were analyzed using statistical paired t-test.

Results: Changes in high-density lipoprotein (HDL), very low-density lipoprotein (VLDL), low-density lipoprotein (LDL) and cholesterol level before and 40 days following the diet administration was statistically significant in cholesterol and ascorbic acid + cholesterol group. In addition, some histological changes and precipitation of cholesterol in liver tissues of cholesterol-fed rabbits were observed.