Neuronal damage of the dorsal hippocampus induced by long-term right common carotid artery occlusion in rats

OBJECTIVE(S) The present study investigated the effect of long-term mild cerebral hypoperfusion induced by permanent unilateral (right) common carotid artery occlusion (UCO) on the dorsal hippocampal neurons in rats. MATERIALS AND METHODS Sixty four male Sprague-Dawley rats aged 4 months were divided into two groups of sham and UCO. These two groups were further divided into 4 sets of histopathological observation periods at 8, 16, 48 and 56 weeks after arterial occlusion. Pathological changes were observed in three regions (CA1, CA3 and DG) of the dorsal hippocampus. RESULTS Significant increase of damaged neurons in CA1 region at 8, 16, 48, and 56 weeks were observed, whereas in CA3 and DG regions it was at 16, 48, and 56 weeks. Gradual increase of damaged neurons was found without significant change in hemodynamic parameters. CONCLUSION Long-term right common carotid artery occlusion in rats induced delay and progressive damage to the dorsal hippocampus with regional vulnerability from CA1 followed by CA3 and DG regions.