Expression of angiotensin II AT2 receptor in the acute phase of stroke in rats.

A male Wistar rat model of stroke (middle cerebral artery occlusion; MCAO) was used to study the angiotensin II (Ang II) receptor subtype 2 (AT2) gene expression by reverse transcription polymerase chain reaction (RT-PCR) and immunohistochemical staining. After permanent occlusion of the middle cerebral artery (MCA), AT2 receptor gene expression was found to increase in the infarct cortex by 2.7-fold (1 day) and 1.7-fold (3 days), respectively. Positive AT2 immunostaining was also observed in the infarct area of the cerebral cortex. Apoptotic markers were detected in the necrotic area of the stroke cerebral cortex 1 day after MCAO. This demonstrated up-regulation of AT2 receptor may be involved in the apoptosis of tissue repair after stroke.