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 (AT 2 ) gene expression by reverse transcription polymerase chain reaction (RT-PCR) and immunohistochemical staining. After permanent occlusion of the middle cerebral artery (MCA), AT 2 receptor gene expression was found to increase in the infarct cortex by 2.7-fold (I day) and 1.7-fold (3 days), respectively. Positive AT 2 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 I day after MCAO. This demonstrated up-regulation of AT 2 receptor may be involved in the apoptosis of tissue repair after stroke.