Abstract

Free radicals are electrically charged molecules that are produced during the course of normal metabolism. They spontaneously attack lipids, proteins, nucleic acids and other biologically important molecules. Polyunsaturated lipids are particularly sensitive to their attack. Free radicals and oxidative stress have been reported to be involved in tissue injury associated with a number of diseases. The present study was done to investigate the effect of vitamin D on cold induced oxidative stress in rats. Rats were divided into control, acute and chronic stress groups with and without vitamin D treatment. Tissue total antioxidant concentration and tissue lipid peroxide were measured in all groups. Statistical analysis was done using the computer software program prism version 3.3. Result showed that the acute cold restraint decreased the total antioxidant levels below the control but there was a significant increase in antioxidant levels of the group in which vitamin D is administered. Chronic cold restraint produces non significant decrease of total antioxidant levels. There was a significant increase of total antioxidant level in chronic cold restraint rats treated vitamin D. Moreover, the chronic cold group with vitamin D produced significant increase of plasma total antioxidant levels above control, acute, chronic groups. The lipid peroxide levels were increased significantly in acute cold restraint group with and without vitamin D as compared to control. Vitamin D produces non significant decrease in lipid peroxide levels in acute and chronic cold restraint group.

Key words: Vitamin D, stress, defense mechanism, animal experimentation.