Angiotensin AT2 receptor protects against cerebral ischemia-induced neuronal injury.

Several lines of clinical and experimental evidence suggest an important role of the renin-angiotensin system in ischemic brain injury although the cellular regulation of the angiotensin AT1 and AT2 receptors and their potential relevance in this condition have not yet been clearly defined. We first assessed the regulation of brain AT1 and AT2 receptors in response to transient unilateral medial cerebral artery occlusion in rats by real-time RT-PCR, Western blot, and immunofluorescence labeling. AT2 receptors in the peri-infarct zone were significantly upregulated 2 days after transient focal cerebral ischemia.