ABSTRACT
Background: Previously it was thought that mercury sulphide in low dose shows good therapeutic effect without producing toxic effects in the human beings. Symptoms like ataxia, speech impairment, visual field constriction, deafness, tremors, mental retardation, coma and even death has been reported due to chronic use of this heavy metal. The aim of our present study is to compare histopathological changes in different parts of brain, so that clinical symptoms following mercury intoxication can be explained. Methods: Freshly prepared sterile solution of mercuric chloride in distilled water (0.33 mg/kg body weight) was orally administered daily to total number of 30 adult albino rats (15 males and 15 females) for a month. 3mm thick sections were taken from cerebrum, cerebellum and hippocampus parts. These sections were processed and then stained by haematoxylin & eosin to be observed in light microscope. Results: Histological pictures of all the three areas were suggestive of multiple foci of necrosis with gliosis. Marked congestion of vessels with perivascular necrosis was also noticed. Increased cellularity of granular layer and molecular layer in cerebellum and hippocampus were seen respectively. Conclusion: The histopathological examination revealed that normal cytoarchitecture of all the three areas of brain were distorted resulting in various neurological disorders.