Focal brainstem infarction in the adult rat

Animal models are required to study the pathogenesis of brainstem ischemia and to develop new therapeutic approaches to promote functional recovery after ischemia in humans. Few models of brainstem ischemia are available, and they show great variability or cause early lethality. New, reliable animal models are therefore needed. By selectively ligating four points of the lower basilar artery, we developed a new focal basilar artery occlusion model that causes a localized brainstem ischemic lesion in female Sprague-Dawley rats. Analysis of ischemic lesion volume and neurological deficits over a period of 28 d showed that the rats present symptoms specific to this type of stroke while the ischemic lesion remains relatively unchanged over time. This procedure allows higher survival rates and extended observation periods compared with other models of brainstem ischemia. The procedure takes ~40 min, can be performed by researchers with basic surgical skills and does not require specialized surgical equipment. This protocol is highly reliable and will be useful to evaluate new therapeutic approaches to promote functional recovery in patients with brainstem ischemia.