Comparative Study of the Effect of Chronic Aluminium Chloride Administration on the Expression of Endothelial Nitric Oxide Synthase in Rat Brain

Background: Aluminium chloride (AlCl3 ) is a known potent environmental neurotoxic agent causing progressive neurodegenerative changes in the brain. Increasing evidence suggests that oxidative stressis strongly related to AlCl 3 neurotoxicity. Endothelial nitric oxide synthase (eNOS) is aniso form of the nitric oxide (NO) synthases family.

Aim of the Work:The current study was carried out to investigate the profile of the expression of eNOS in differentbrain regionsfollowing chronic aluminium chloride administration.

Materials and Method: Twelve adult male albinorats were divided equally into two groups. Group I was the untreated control, groups II was given Alcl 3 (100 mg/kg body weight) orally daily 42 days. At the end of the experiment, rats were killed by decapitation under anaesthesia. The brains were removed and processed for immunohistochemistry using antibody raised against eNOS.

Results:By comparison to the untreated control, Alcl3 treated rats showed significant (P<0.001) increase of eNOS expression in capillaries of cerebral cortex, hippocampus and cerebellum. In addition, there was significant (P<0.001) increase of eNOSexpression in hippocampus when compared to cortex and cerebellum.

Conclusion:These data provide further evidence that chronic exposure to aluminium chloride potentiate oxidative stress with subsequente NOS induction in different brain regions with more hippocampal affection.