Rotenone induced neurotoxicity in rat brain areas: a histopathological study

Rotenone a pesticide is known to induce neurotoxicity. In earlier study we correlated rotenone induced biochemical changes and cerebral damage in brain areas with neuromuscular coordination in rats. The present study involves investigation of rotenone induced histopathological changes in the brain areas, viz. striatum (STR) and substantia nigra (SN) using HE (hematoxylin and eosin) and CV (Cresyl Violet) staining after 1, 7, and 14 day of unilateral intranigral administration of rotenone (3, 6 and 12 μg/5 μl) in adult male SD rats. Significant morphological changes in cell area or shape were shown by HE staining. The neuronal degeneration was shown by distorted neuronal cells, shrinkage of nuclei, dark staining in the regions of rotenone treated animals by CV staining. Rota rod test demonstrated significant impairment in motor coordination after 14 days of treatment along with decreased GSH and increased MDA in STR and mid brain (MB). The study inferred rotenone causes neuronal damage which is evident by histopathological changes, impaired neuromuscular coordination and biochemical changes. The pattern of histopathological alterations corresponds with behavioral and biochemical manifestations.