Comparison of Bilateral Carotid Artery Occlusion and Stenosis in Inducing Behaviour and Structural Changes in Rodents

Abstract

This study aimed to compare the effects of bilateral common carotid artery occlusion (BCCAO) and bilateral carotid artery stenosis (BCAS) on brain function and structure in rodents. Adult male Sprague-Dawley rats and C57BL/6 mice were randomly assigned to either the BCCAO or sham group and the BCAS or sham group, respectively. Neurobehavioral assessments were conducted using various tests, and histological examination was performed to evaluate brain structure. Both surgeries induced white matter damage, with BCCAO mainly affecting the hippocampus and BCAS affecting the blood flow. BCCAO rats exhibited anxiety-like behaviors and cognitive impairment at week 8, while BCAS mice showed significant cognitive deficits at week 4. Both surgeries caused cellular responses to white matter damage, with increased astrocytes and microglial/macrophagemarkers observed in the corpus callosum region. Physical growth and development were not significantly impacted, and there was no difference in bilateral cerebral blood flow between the surgery and sham groups. In conclusion, both models induced significant cognitive impairment and white matter damage. BCCAO induced anxiety-like behaviors at a later stage compared to BCAS, which could help researchers study the underlying mechanisms of chronic cerebral ischemia and drug evaluation.