Background: It has been detected that general population is exposed to many products of daily used that contain formaldehyde. Numerous studies revealed that formaldehyde- induced major health problems affecting all the body organs especially the liver. Recent studies have shown melatonin to be an antioxidant substance which has been used for the treatment of liver diseases.
Aim of work: This study aimed to investigate histological and biochemical changes in the livers of formaldehyde exposed rats and possible effects of melatonin hormone on these changes.
Material and Methods: Eighteen healthy adult male albino rats were studied. The animals were divided into three main equal groups, six rats each:
Group I: (control group) rats were given tap water.
Group II: rats received 2ml of 0.1% of formaldehyde.
Group III: rats received 2ml of 0.1% of formaldehyde with melatonin (25 mg/kg) diluted in 0.9% of Nacl. After 8 weeks all animals of the three groups were sacrificed. Liver functions were assessed both biochemically and histologically using both light and electron microscopes.
Results: The present study demonstrated variable degrees of hepatic affection after administration of formaldehyde in rats of group II, manifested as biochemical and histological changes. The plasma level of (SGOT) and (SGPT) showed a significant increase. Rats of group III treated with melatonin showed considerable preservation of the liver histology.
Conclusion: Melatonin had a protective role on the liver which may improve the toxic damaging effect of the formaldehyde on the liver cells.