Background: Formaldehyde (F) is a chemical component that has an extensive usage on fixation of tissues and produces different types of reactive oxygen species (ROS) in our body. Studies have shown that long exposure to F damages the eyes, nose and throat; in addition it has adverse effects on body organs such as the urinary system. Vitamins can reduce free ROS.

Objectives: The aim of this study was evaluating the protective effect of vitamin E on the kidney damaged by formaldehyde.

Materials and Methods: Male adult wistar rats were divided into three groups. Group A (control): rats received vehicle (normal saline) for two weeks. Group E1 (formaldehyde): rats received formaldehyde (10 mg/kg) for two weeks. Group E2 (formaldehyde + vitamin E): rats received formaldehyde (10 mg/kg) and vitamin E (30 mg/kg) for two weeks. After two weeks, all rats were killed, and the kidneys were dissected and processed for routine histological staining.

Results: Comparison of the control and formaldehyde groups with the vitamin E group revealed that there were significant differences in lumen size and nuclear color of proximal tubules in rats treated by vitamin E (P < 0.05). Cell degeneration, lumen size, number and size of nucleus of distal tubules were statistically different among the three groups. In the vitamin E treated group observed histological changes were improved compared to the formaldehyde group.

Conclusions: According to the results of this study, vitamin E probably improves the harmful effects of formaldehyde on rat kidney tissue.