Effect of melatonin on neuronal nitric oxide synthase expressing cells in the brain following global cerebral ischemia

Document Type



Brain and Mind Institute


Nitric oxide can be either neuroprotective or neurotoxic depending on which isoform is expressed during global cerebral ischemia. The chronological and spatial distribution and expression of neuronal nitric oxide synthase cells in the brain following ischemia and melatonin administration was studied in Sprague-Dawley rats. Global cerebral ischemia was induced by common carotid artery occlusion for 10 min followed by reperfusion. The rats were divided into three experimental groups. One group received 5 mg kg" melatonin 30 min before ischemia, another group received the same dose of melatonin post-ischemia and a third NO ischemia NO melatonin control group. All animals were euthanized 72 h post ischemia, perfusion-fixed with 4% paraformaldehyde in phosphate buffer and the brains removed. Immunopositive neuronal Nitric Oxide Synthase (nNOS) expression was observed in the cerebral cortex


This work was published before the author joined Aga Khan University.